I may have this figured out. If anybody has this problem, try this and report back. The problem occurs when you have the plugin for an older camera (4mp in my case, don't know if that matters), then get a newer camera that needs a different plugin, which you install. Then you want to login into the older cameras, and reinstall their plugin, which now crashes.
The fix:
1. Go to directory c:\program files\webrec\3.0.0.3 (this is where the plugin files are stored)
2. Delete the files fisheye.dll and fisheyeCtrl.dll
The older camera plugin will hopefully now work. If it doesn't, try Plan B:
1. In the webec\3.0.0.3 directory, run uninst.exe. The directory should now be empty. If it isn't, delete any remaining files.
2. Install the older camera plugin, which will hopefully now work.