I dunno. So you're not having that problem with all skins, just some? Just off the top of my uninformed head, if you haven't already, you first might try deleting the problem skins and then reinstalling them with a new download and see if that makes any difference. And then of course, if the problem still persists, there's the usual troubleshooting with any app, uninstall and reinstall the app itself and see if that knocks the kinks out. (You may want to back up any skins you want to keep when you do that. I haven't lost any skins with an uninstall of WindowBlinds but some say they have.) But if it's only with certain skins I'd definitely first try deleting and reinstalling the skins to see if that works before uninstalling/reinstalling the app itself.
Also, did you do a clean install of WB4? Or did you install 4 over 3.5 (if you had it)? Sometimes a clean install is recommended. I uninstalled 3.5 before installing WB 4 and so far it's been ok for me.
Here's some instructions on how to set up a newsgroup account in OE (look after the MS newserver links): http://insideoe.tomsterdam.com/resources.htm
Instead of using MS newserver name, use news.stardock.com
Then you can subscribe to the newsgroups. Like windowblinds development and windowblinds development binaries (where you can post screenshots).
If you can't resolve the issue, don't forget to also email stardock support directly. Sometimes it may take a few days to get back to you depending on their workload, just so you know. Good luck.