Thanks, I should have guessed I missed something - but not among racks it seems.
Nothing in manual, and only looking I found key command for it.
And there were notes on tracks as well, how lovely.
For those having Sonar there is a folder Cakewalk Content which also hols Track Icons - and there are hundreds of images in full color 96x96 px 24 bit all by instrument folder.
I treid without any conversion, and works fine - set intensity to zero and you get nice color.
Though I will remove and make alpha-channel of background for it to become transparent.
Not for redistribution of course, just a tip for Sonar owners.