unable to npm run dist on win8 x64 - imagemin issue?

[netalex]

it seems that grunt on windows 8 x64 expect to use some linux\osx comnents only, that in install phase where signaled as warnings.

grunt serve:dist

Loading "imagemin.js" tasks...ERROR

Error: Cannot find module 'imagemin-optipng'

Running "serve:dist" (serve) task
(node:16632) DeprecationWarning: process.EventEmitter is deprecated. Use require('events') instead.

Running "clean:dist" (clean) task
Cleaning .tmp...OK

Running "concurrent:dist" (concurrent) task
Warning: Loading "imagemin.js" tasks...ERROR

Error: Cannot find module 'imagemin-optipng'
Warning: Task "imagemin" not found. Use --force to continue.

Aborted due to warnings.

Execution Time (2016-09-24 17:41:14 UTC)
loading tasks 15ms ■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■ 100%
Total 15ms Use --force to continue.

Aborted due to warnings.

Execution Time (2016-09-24 17:41:05 UTC)
clean:dist 94ms ■ 1%
concurrent:dist 8.7s ■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■ 99%
Total 8.8s