Must be a problem with the icon theme.. Try changing your icon theme and see if it works.
Btw did you notice any odd changes in your other apps like ROX-Filer??
And to answer your second question, I think Lucid has a Menu Entry called "Remove Builtin Packages"
or something like that and delete the WMs you don't need. Sorry I'm not on Lucid now, so I can't check.. I'll get back to you when I get Lucid again