make sure you back-up runtime/geometries, textures & libraries. had another idea on how to fix window without a re-install, get someone to send a ui-dot file (with at least one ui-dot set. In case you don't know about ui-dots (I didn't at first) they are programable buttons that you can configure for your workspace setting, go to ui-dots click a button, mess aound with the workspace, if you want the original back, click that same ui-button, your workspace is back like magic. (again, don't know if this will work with propack)