diff --git a/eng/Version.Details.xml b/eng/Version.Details.xml
index 4bbbd2ba..86c9c21d 100644
--- a/eng/Version.Details.xml
+++ b/eng/Version.Details.xml
@@ -3,9 +3,9 @@
   <ProductDependencies>
   </ProductDependencies>
   <ToolsetDependencies>
-    <Dependency Name="Microsoft.DotNet.Arcade.Sdk" Version="11.0.0-beta.26211.1">
+    <Dependency Name="Microsoft.DotNet.Arcade.Sdk" Version="11.0.0-beta.26225.1">
       <Uri>https://github.com/dotnet/arcade</Uri>
-      <Sha>a08169b890573cfd7f949ea9062c86a4db1aab1b</Sha>
+      <Sha>e822416a9237f26c9a62562fa6ce0f707da1dfe3</Sha>
     </Dependency>
   </ToolsetDependencies>
 </Dependencies>
diff --git a/eng/common/core-templates/job/onelocbuild.yml b/eng/common/core-templates/job/onelocbuild.yml
index eefed3b6..86ea9f63 100644
--- a/eng/common/core-templates/job/onelocbuild.yml
+++ b/eng/common/core-templates/job/onelocbuild.yml
@@ -22,6 +22,7 @@ parameters:
   GitHubOrg: dotnet
   MirrorRepo: ''
   MirrorBranch: main
+  xLocCustomPowerShellScript: ''
   condition: ''
   JobNameSuffix: ''
   is1ESPipeline: ''
@@ -97,6 +98,8 @@ jobs:
           gitHubOrganization: ${{ parameters.GitHubOrg }}
           mirrorRepo: ${{ parameters.MirrorRepo }}
           mirrorBranch: ${{ parameters.MirrorBranch }}
+        ${{ if ne(parameters.xLocCustomPowerShellScript, '') }}:
+          xLocCustomPowerShellScript: ${{ parameters.xLocCustomPowerShellScript }}
       condition: ${{ parameters.condition }}
 
     # Copy the locProject.json to the root of the Loc directory, then publish a pipeline artifact
diff --git a/eng/common/core-templates/post-build/post-build.yml b/eng/common/core-templates/post-build/post-build.yml
index fcf40d1d..8aa86e30 100644
--- a/eng/common/core-templates/post-build/post-build.yml
+++ b/eng/common/core-templates/post-build/post-build.yml
@@ -225,7 +225,7 @@ stages:
         displayName: Validate
         inputs:
           filePath: eng\common\sdk-task.ps1
-          arguments: -task SigningValidation -restore
+          arguments: -task SigningValidation -restore -msbuildEngine dotnet
             /p:PackageBasePath='$(Build.ArtifactStagingDirectory)/PackageArtifacts'
             /p:SignCheckExclusionsFile='$(System.DefaultWorkingDirectory)/eng/SignCheckExclusionsFile.txt'
             ${{ parameters.signingValidationAdditionalParameters }}
diff --git a/eng/common/cross/toolchain.cmake b/eng/common/cross/toolchain.cmake
index ff2dfdb4..99d6dfe8 100644
--- a/eng/common/cross/toolchain.cmake
+++ b/eng/common/cross/toolchain.cmake
@@ -225,13 +225,19 @@ elseif(ILLUMOS)
     locate_toolchain_exec(g++ CMAKE_CXX_COMPILER)
 elseif(HAIKU)
     set(CMAKE_SYSROOT "${CROSS_ROOTFS}")
-    set(CMAKE_PROGRAM_PATH "${CMAKE_PROGRAM_PATH};${CROSS_ROOTFS}/cross-tools-x86_64/bin")
     set(CMAKE_SYSTEM_PREFIX_PATH "${CROSS_ROOTFS}")
     set(CMAKE_C_STANDARD_LIBRARIES "${CMAKE_C_STANDARD_LIBRARIES} -lssp")
     set(CMAKE_CXX_STANDARD_LIBRARIES "${CMAKE_CXX_STANDARD_LIBRARIES} -lssp")
 
-    locate_toolchain_exec(gcc CMAKE_C_COMPILER)
-    locate_toolchain_exec(g++ CMAKE_CXX_COMPILER)
+    if ($ENV{CCC_CC} MATCHES ".*gcc.*")
+        set(CMAKE_PROGRAM_PATH "${CMAKE_PROGRAM_PATH};${CROSS_ROOTFS}/cross-tools-x86_64/bin")
+        locate_toolchain_exec(gcc CMAKE_C_COMPILER)
+        locate_toolchain_exec(g++ CMAKE_CXX_COMPILER)
+    else()
+        set(CMAKE_C_COMPILER_EXTERNAL_TOOLCHAIN "${CROSS_ROOTFS}/cross-tools-x86_64")
+        set(CMAKE_CXX_COMPILER_EXTERNAL_TOOLCHAIN "${CROSS_ROOTFS}/cross-tools-x86_64")
+        set(CMAKE_ASM_COMPILER_EXTERNAL_TOOLCHAIN "${CROSS_ROOTFS}/cross-tools-x86_64")
+    endif()
 
     # let CMake set up the correct search paths
     include(Platform/Haiku)
diff --git a/eng/common/sdk-task.ps1 b/eng/common/sdk-task.ps1
index 64fd2f8a..68119de6 100644
--- a/eng/common/sdk-task.ps1
+++ b/eng/common/sdk-task.ps1
@@ -22,7 +22,7 @@ $warnAsError = if ($noWarnAsError) { $false } else { $true }
 
 function Print-Usage() {
   Write-Host "Common settings:"
-  Write-Host "  -task <value>           Name of Arcade task (name of a project in SdkTasks directory of the Arcade SDK package)"
+  Write-Host "  -task <value>           Name of Arcade task (name of a project in toolset directory of the Arcade SDK package)"
   Write-Host "  -restore                Restore dependencies"
   Write-Host "  -verbosity <value>      Msbuild verbosity: q[uiet], m[inimal], n[ormal], d[etailed], and diag[nostic]"
   Write-Host "  -help                   Print help and exit"
diff --git a/eng/common/sdk-task.sh b/eng/common/sdk-task.sh
index 3270f83f..1cf71bb2 100644
--- a/eng/common/sdk-task.sh
+++ b/eng/common/sdk-task.sh
@@ -2,7 +2,7 @@
 
 show_usage() {
     echo "Common settings:"
-    echo "  --task <value>           Name of Arcade task (name of a project in SdkTasks directory of the Arcade SDK package)"
+    echo "  --task <value>           Name of Arcade task (name of a project in toolset directory of the Arcade SDK package)"
     echo "  --restore                Restore dependencies"
     echo "  --verbosity <value>      Msbuild verbosity: q[uiet], m[inimal], n[ormal], d[etailed], and diag[nostic]"
     echo "  --help                   Print help and exit"
diff --git a/eng/common/tools.ps1 b/eng/common/tools.ps1
index e28db6c7..b5d13be7 100644
--- a/eng/common/tools.ps1
+++ b/eng/common/tools.ps1
@@ -168,6 +168,12 @@ function InitializeDotNetCli([bool]$install, [bool]$createSdkLocationFile) {
     $env:DOTNET_CLI_TELEMETRY_OPTOUT=1
   }
 
+  # Keep repo builds isolated from machine-installed SDK state and workload advertising.
+  # This avoids preview SDK builds picking up mismatched workloads on CI images.
+  $env:DOTNET_MULTILEVEL_LOOKUP = '0'
+  $env:DOTNET_SKIP_FIRST_TIME_EXPERIENCE = '1'
+  $env:DOTNET_CLI_WORKLOAD_UPDATE_NOTIFY_DISABLE = '1'
+
   # Find the first path on %PATH% that contains the dotnet.exe
   if ($useInstalledDotNetCli -and (-not $globalJsonHasRuntimes) -and ($env:DOTNET_INSTALL_DIR -eq $null)) {
     $dotnetExecutable = GetExecutableFileName 'dotnet'
@@ -230,6 +236,9 @@ function InitializeDotNetCli([bool]$install, [bool]$createSdkLocationFile) {
   Write-PipelinePrependPath -Path $dotnetRoot
 
   Write-PipelineSetVariable -Name 'DOTNET_NOLOGO' -Value '1'
+  Write-PipelineSetVariable -Name 'DOTNET_MULTILEVEL_LOOKUP' -Value '0'
+  Write-PipelineSetVariable -Name 'DOTNET_SKIP_FIRST_TIME_EXPERIENCE' -Value '1'
+  Write-PipelineSetVariable -Name 'DOTNET_CLI_WORKLOAD_UPDATE_NOTIFY_DISABLE' -Value '1'
 
   return $global:_DotNetInstallDir = $dotnetRoot
 }
@@ -480,7 +489,6 @@ function LocateVisualStudio([object]$vsRequirements = $null){
   if (Get-Member -InputObject $GlobalJson.tools -Name 'vswhere') {
     $vswhereVersion = $GlobalJson.tools.vswhere
   } else {
-    # keep this in sync with the VSWhereVersion in DefaultVersions.props
     $vswhereVersion = '3.1.7'
   }
 
@@ -615,7 +623,17 @@ function GetNuGetPackageCachePath() {
 
 # Returns a full path to an Arcade SDK task project file.
 function GetSdkTaskProject([string]$taskName) {
-  return Join-Path (Split-Path (InitializeToolset) -Parent) "SdkTasks\$taskName.proj"
+  $toolsetDir = Split-Path (InitializeToolset) -Parent
+  $proj = Join-Path $toolsetDir "$taskName.proj"
+  if (Test-Path $proj) {
+    return $proj
+  }
+  # TODO: Remove this fallback once all supported versions use the new layout.
+  $legacyProj = Join-Path $toolsetDir "SdkTasks\$taskName.proj"
+  if (Test-Path $legacyProj) {
+    return $legacyProj
+  }
+  throw "Unable to find $taskName.proj in toolset at: $toolsetDir"
 }
 
 function InitializeNativeTools() {
@@ -652,13 +670,18 @@ function InitializeToolset() {
   $nugetCache = GetNuGetPackageCachePath
 
   $toolsetVersion = Read-ArcadeSdkVersion
-  $toolsetLocationFile = Join-Path $ToolsetDir "$toolsetVersion.txt"
+  $toolsetToolsDir = Join-Path $ToolsetDir $toolsetVersion
 
-  if (Test-Path $toolsetLocationFile) {
-    $path = Get-Content $toolsetLocationFile -TotalCount 1
-    if (Test-Path $path) {
-      return $global:_InitializeToolset = $path
-    }
+  # Check if the toolset has already been extracted
+  $toolsetBuildProj = $null
+  $buildProjPath = Join-Path $toolsetToolsDir 'Build.proj'
+
+  if (Test-Path $buildProjPath) {
+    $toolsetBuildProj = $buildProjPath
+  }
+
+  if ($toolsetBuildProj -ne $null) {
+    return $global:_InitializeToolset = $toolsetBuildProj
   }
 
   if (-not $restore) {
@@ -666,21 +689,50 @@ function InitializeToolset() {
     ExitWithExitCode 1
   }
 
-  $buildTool = InitializeBuildTool
+  $downloadArgs = @("package", "download", "Microsoft.DotNet.Arcade.Sdk@$toolsetVersion", "--verbosity", "minimal", "--prerelease", "--output", "$nugetCache")
+  $nugetConfig = $env:NUGET_CONFIG
+  if (-not $nugetConfig) {
+    # Search for any variation of nuget.config in the RepoRoot
+    $configFile = Get-ChildItem -Path $RepoRoot -File | Where-Object { $_.Name -ieq "nuget.config" } | Select-Object -First 1
 
-  $proj = Join-Path $ToolsetDir 'restore.proj'
-  $bl = if ($binaryLog) { '/bl:' + (Join-Path $LogDir 'ToolsetRestore.binlog') } else { '' }
+    if ($configFile) {
+        $nugetConfig = $configFile.FullName
+    }
+  }
 
-  '<Project Sdk="Microsoft.DotNet.Arcade.Sdk"/>' | Set-Content $proj
+  if ($nugetConfig) {
+    $downloadArgs += "--configfile"
+    $downloadArgs += $nugetConfig
+  }
+  DotNet @downloadArgs
 
-  MSBuild-Core $proj $bl /t:__WriteToolsetLocation /clp:ErrorsOnly`;NoSummary /p:__ToolsetLocationOutputFile=$toolsetLocationFile
+  $packageDir = Join-Path $nugetCache (Join-Path 'microsoft.dotnet.arcade.sdk' $toolsetVersion)
+  $packageToolsetDir = Join-Path $packageDir 'toolset'
+  $packageToolsDir = Join-Path $packageDir 'tools'
 
-  $path = Get-Content $toolsetLocationFile -Encoding UTF8 -TotalCount 1
-  if (!(Test-Path $path)) {
-    throw "Invalid toolset path: $path"
+  # TODO: Remove the tools/ check once all supported versions have the toolset folder.
+  if (!(Test-Path $packageToolsetDir) -and !(Test-Path $packageToolsDir)) {
+    Write-PipelineTelemetryError -Category 'InitializeToolset' -Message "Arcade SDK package does not contain a toolset or tools folder: $packageDir"
+    ExitWithExitCode 3
   }
 
-  return $global:_InitializeToolset = $path
+  New-Item -ItemType Directory -Path $toolsetToolsDir -Force | Out-Null
+
+  # Copy toolset if present at the package root (new layout), otherwise fall back to tools
+  if (Test-Path $packageToolsetDir) {
+    Copy-Item -Path "$packageToolsetDir\*" -Destination $toolsetToolsDir -Recurse -Force
+  } else {
+    # TODO: Remove this fallback once all supported versions have the toolset folder.
+    Copy-Item -Path "$packageToolsDir\*" -Destination $toolsetToolsDir -Recurse -Force
+  }
+
+  if (Test-Path $buildProjPath) {
+    $toolsetBuildProj = $buildProjPath
+  } else {
+    throw "Unable to find Build.proj in toolset at: $toolsetToolsDir"
+  }
+
+  return $global:_InitializeToolset = $toolsetBuildProj
 }
 
 function ExitWithExitCode([int] $exitCode) {
@@ -741,6 +793,40 @@ function MSBuild() {
   MSBuild-Core @args
 }
 
+#
+# Executes a dotnet command with arguments passed to the function.
+# Terminates the script if the command fails.
+#
+function DotNet() {
+  $dotnetRoot = InitializeDotNetCli -install:$restore
+  $dotnetPath = Join-Path $dotnetRoot (GetExecutableFileName 'dotnet')
+
+  $cmdArgs = ""
+  foreach ($arg in $args) {
+    if ($null -ne $arg -and $arg.Trim() -ne "") {
+      if ($arg.EndsWith('\')) {
+        $arg = $arg + "\"
+      }
+      $cmdArgs += " `"$arg`""
+    }
+  }
+
+  $env:ARCADE_BUILD_TOOL_COMMAND = "`"$dotnetPath`" $cmdArgs"
+
+  $exitCode = Exec-Process $dotnetPath $cmdArgs
+
+  if ($exitCode -ne 0) {
+    Write-Host "dotnet command failed with exit code $exitCode. Check errors above." -ForegroundColor Red
+
+    if ($ci -and $env:SYSTEM_TEAMPROJECT -ne $null -and !$fromVMR) {
+      Write-PipelineSetResult -Result "Failed" -Message "dotnet command execution failed."
+      ExitWithExitCode 0
+    } else {
+      ExitWithExitCode $exitCode
+    }
+  }
+}
+
 #
 # Executes msbuild (or 'dotnet msbuild') with arguments passed to the function.
 # The arguments are automatically quoted.
@@ -765,6 +851,10 @@ function MSBuild-Core() {
 
   $cmdArgs = "$($buildTool.Command) /m /nologo /clp:Summary /v:$verbosity /nr:$nodeReuse /p:ContinuousIntegrationBuild=$ci"
 
+  if ($ci -and $buildTool.Tool -eq 'dotnet') {
+    $cmdArgs += ' /p:MSBuildEnableWorkloadResolver=false'
+  }
+
   # Add -mt flag for MSBuild multithreaded mode if enabled via environment variable
   if ($env:MSBUILD_MT_ENABLED -eq "1") {
     $cmdArgs += ' -mt'
@@ -875,6 +965,12 @@ Create-Directory $ToolsetDir
 Create-Directory $TempDir
 Create-Directory $LogDir
 
+# Direct MSBuild crash diagnostics (MSB4166 failure.txt files) to a known location
+# under artifacts/log so they are captured as build artifacts in CI.
+if (-not $env:MSBUILDDEBUGPATH) {
+  $env:MSBUILDDEBUGPATH = Join-Path $LogDir 'MsbuildDebugLogs'
+}
+
 Write-PipelineSetVariable -Name 'Artifacts' -Value $ArtifactsDir
 Write-PipelineSetVariable -Name 'Artifacts.Toolset' -Value $ToolsetDir
 Write-PipelineSetVariable -Name 'Artifacts.Log' -Value $LogDir
diff --git a/eng/common/tools.sh b/eng/common/tools.sh
index 1e37fd95..c0f0b13c 100644
--- a/eng/common/tools.sh
+++ b/eng/common/tools.sh
@@ -126,6 +126,12 @@ function InitializeDotNetCli {
     export DOTNET_CLI_TELEMETRY_OPTOUT=1
   fi
 
+  # Keep repo builds isolated from machine-installed SDK state and workload advertising.
+  # This avoids preview SDK builds picking up mismatched workloads on CI images.
+  export DOTNET_MULTILEVEL_LOOKUP=0
+  export DOTNET_SKIP_FIRST_TIME_EXPERIENCE=1
+  export DOTNET_CLI_WORKLOAD_UPDATE_NOTIFY_DISABLE=1
+
   # LTTNG is the logging infrastructure used by Core CLR. Need this variable set
   # so it doesn't output warnings to the console.
   export LTTNG_HOME="$HOME"
@@ -171,6 +177,9 @@ function InitializeDotNetCli {
   Write-PipelinePrependPath -path "$dotnet_root"
 
   Write-PipelineSetVariable -name "DOTNET_NOLOGO" -value "1"
+  Write-PipelineSetVariable -name "DOTNET_MULTILEVEL_LOOKUP" -value "0"
+  Write-PipelineSetVariable -name "DOTNET_SKIP_FIRST_TIME_EXPERIENCE" -value "1"
+  Write-PipelineSetVariable -name "DOTNET_CLI_WORKLOAD_UPDATE_NOTIFY_DISABLE" -value "1"
 
   # return value
   _InitializeDotNetCli="$dotnet_root"
@@ -411,15 +420,18 @@ function InitializeToolset {
   ReadGlobalVersion "Microsoft.DotNet.Arcade.Sdk"
 
   local toolset_version=$_ReadGlobalVersion
-  local toolset_location_file="$toolset_dir/$toolset_version.txt"
+  local toolset_tools_dir="$toolset_dir/$toolset_version"
 
-  if [[ -a "$toolset_location_file" ]]; then
-    local path=`cat "$toolset_location_file"`
-    if [[ -a "$path" ]]; then
-      # return value
-      _InitializeToolset="$path"
-      return
-    fi
+  # Check if the toolset has already been extracted
+  local toolset_build_proj=""
+  if [[ -a "$toolset_tools_dir/Build.proj" ]]; then
+    toolset_build_proj="$toolset_tools_dir/Build.proj"
+  fi
+
+  if [[ -n "$toolset_build_proj" ]]; then
+    # return value
+    _InitializeToolset="$toolset_build_proj"
+    return
   fi
 
   if [[ "$restore" != true ]]; then
@@ -427,20 +439,45 @@ function InitializeToolset {
     ExitWithExitCode 2
   fi
 
-  local proj="$toolset_dir/restore.proj"
+  local download_args=("package" "download" "Microsoft.DotNet.Arcade.Sdk@$toolset_version" "--verbosity" "minimal" "--prerelease" "--output" "$_GetNuGetPackageCachePath")
+  local nuget_config="${NUGET_CONFIG:-}"
+  if [[ -z "$nuget_config" ]]; then
+    # Search for any variation of nuget.config in the RepoRoot
+    local found_config
+    found_config=$(find "$repo_root" -maxdepth 1 -type f -iname "nuget.config" -print -quit)
 
-  local bl=""
-  if [[ "$binary_log" == true ]]; then
-    bl="/bl:$log_dir/ToolsetRestore.binlog"
+    if [[ -n "$found_config" ]]; then
+      nuget_config="$found_config"
+    fi
   fi
 
-  echo '<Project Sdk="Microsoft.DotNet.Arcade.Sdk"/>' > "$proj"
-  MSBuild-Core "$proj" $bl /t:__WriteToolsetLocation /clp:ErrorsOnly\;NoSummary /p:__ToolsetLocationOutputFile="$toolset_location_file"
+  if [[ -n "$nuget_config" ]]; then
+    download_args+=("--configfile" "$nuget_config")
+  fi
+  DotNet "${download_args[@]}"
 
-  local toolset_build_proj=`cat "$toolset_location_file"`
+  local package_dir="$_GetNuGetPackageCachePath/microsoft.dotnet.arcade.sdk/$toolset_version"
 
-  if [[ ! -a "$toolset_build_proj" ]]; then
-    Write-PipelineTelemetryError -category 'Build' "Invalid toolset path: $toolset_build_proj"
+  # TODO: Remove the tools/ check once all supported versions have the toolset folder.
+  if [[ ! -d "$package_dir/toolset" && ! -d "$package_dir/tools" ]]; then
+    Write-PipelineTelemetryError -category 'InitializeToolset' "Arcade SDK package does not contain a toolset or tools folder: $package_dir"
+    ExitWithExitCode 3
+  fi
+
+  mkdir -p "$toolset_tools_dir"
+
+  # Copy toolset if present at the package root (new layout), otherwise fall back to tools
+  if [[ -d "$package_dir/toolset" ]]; then
+    cp -r "$package_dir/toolset/." "$toolset_tools_dir"
+  else
+    # TODO: Remove this fallback once all supported versions have the toolset folder.
+    cp -r "$package_dir/tools/." "$toolset_tools_dir"
+  fi
+
+  if [[ -a "$toolset_tools_dir/Build.proj" ]]; then
+    toolset_build_proj="$toolset_tools_dir/Build.proj"
+  else
+    Write-PipelineTelemetryError -category 'Build' "Unable to find Build.proj in toolset at: $toolset_tools_dir"
     ExitWithExitCode 3
   fi
 
@@ -462,6 +499,26 @@ function StopProcesses {
   return 0
 }
 
+function DotNet {
+  InitializeDotNetCli $restore
+
+  local dotnet_path="$_InitializeDotNetCli/dotnet"
+
+  export ARCADE_BUILD_TOOL_COMMAND="$dotnet_path $@"
+
+  "$dotnet_path" "$@" || {
+    local exit_code=$?
+    echo "dotnet command failed with exit code $exit_code. Check errors above."
+
+    if [[ "$ci" == true && -n ${SYSTEM_TEAMPROJECT:-} && "$from_vmr" != true ]]; then
+      Write-PipelineSetResult -result "Failed" -message "dotnet command execution failed."
+      ExitWithExitCode 0
+    else
+      ExitWithExitCode $exit_code
+    fi
+  }
+}
+
 function MSBuild {
   local args=( "$@" )
   if [[ "$pipelines_log" == true ]]; then
@@ -542,7 +599,12 @@ function MSBuild-Core {
     warnnotaserror_switch="/warnnotaserror:$warn_not_as_error /p:AdditionalWarningsNotAsErrors=$warn_not_as_error"
   fi
 
-  RunBuildTool "$_InitializeBuildToolCommand" /m /nologo /clp:Summary /v:$verbosity /nr:$node_reuse $warnaserror_switch $mt_switch $warnnotaserror_switch /p:TreatWarningsAsErrors=$warn_as_error /p:ContinuousIntegrationBuild=$ci "$@"
+  local workload_resolver_switch=""
+  if [[ "$ci" == true && -n "${_InitializeBuildToolCommand:-}" ]]; then
+    workload_resolver_switch="/p:MSBuildEnableWorkloadResolver=false"
+  fi
+
+  RunBuildTool "$_InitializeBuildToolCommand" /m /nologo /clp:Summary /v:$verbosity /nr:$node_reuse $warnaserror_switch $mt_switch $warnnotaserror_switch $workload_resolver_switch /p:TreatWarningsAsErrors=$warn_as_error /p:ContinuousIntegrationBuild=$ci "$@"
 }
 
 function GetDarc {
@@ -559,8 +621,22 @@ function GetDarc {
 
 # Returns a full path to an Arcade SDK task project file.
 function GetSdkTaskProject {
-  taskName=$1
-  echo "$(dirname $_InitializeToolset)/SdkTasks/$taskName.proj"
+  local taskName=$1
+  local toolsetDir
+  toolsetDir="$(dirname "$_InitializeToolset")"
+  local proj="$toolsetDir/$taskName.proj"
+  if [[ -a "$proj" ]]; then
+    echo "$proj"
+    return
+  fi
+  # TODO: Remove this fallback once all supported versions use the new layout.
+  local legacyProj="$toolsetDir/SdkTasks/$taskName.proj"
+  if [[ -a "$legacyProj" ]]; then
+    echo "$legacyProj"
+    return
+  fi
+  Write-PipelineTelemetryError -category 'Build' "Unable to find $taskName.proj in toolset at: $toolsetDir"
+  ExitWithExitCode 3
 }
 
 ResolvePath "${BASH_SOURCE[0]}"
@@ -598,6 +674,12 @@ mkdir -p "$toolset_dir"
 mkdir -p "$temp_dir"
 mkdir -p "$log_dir"
 
+# Direct MSBuild crash diagnostics (MSB4166 failure.txt files) to a known location
+# under artifacts/log so they are captured as build artifacts in CI.
+if [[ -z "${MSBUILDDEBUGPATH:-}" ]]; then
+  export MSBUILDDEBUGPATH="$log_dir/MsbuildDebugLogs"
+fi
+
 Write-PipelineSetVariable -name "Artifacts" -value "$artifacts_dir"
 Write-PipelineSetVariable -name "Artifacts.Toolset" -value "$toolset_dir"
 Write-PipelineSetVariable -name "Artifacts.Log" -value "$log_dir"
diff --git a/global.json b/global.json
index 1f3efd2f..f49fa291 100644
--- a/global.json
+++ b/global.json
@@ -1,11 +1,11 @@
 {
   "tools": {
-    "dotnet": "11.0.100-preview.3.26170.106"
+    "dotnet": "11.0.100-preview.4.26210.111"
   },
   "test": {
     "runner": "Microsoft.Testing.Platform"
   },
   "msbuild-sdks": {
-    "Microsoft.DotNet.Arcade.Sdk": "11.0.0-beta.26211.1"
+    "Microsoft.DotNet.Arcade.Sdk": "11.0.0-beta.26225.1"
   }
 }