Thanks for the update
gninfo and happy to hear you got the problem resolved.
Interesting resolution.
Yes, the newest versions of WW have the skins and other updatable data stored in the user's Windows User Profile folder rather than the install folder. It makes it easier for multi user systems to share one copy of WW rather than each user having their own. And is effective when users use limited accounts rather than admin ones.
Since you now know where WW was storing your files when you were having the problem you could try deleting all the files in the old Windows User Profile WW folder then switch the WW option back to storing it's files there and see if the problem reoccurs.
Maybe if you zip up all the files in the old Windows User Profile WW folder you could send them to Mike and maybe he could see what file was corrupted and causing the problem. Then again maybe he doesn't have the time. Check with him first.

Maybe the old location was on a spot on the hd that had a bad cluster. A CHKDSK run might prove interesting.