Hmm... if reinstalling doesn't work, maybe you can delete the "Version.txt" file to force an update. Also, have you checked if your antivirus deleted the files during the installation? Some antiviruses (like mine) can be jerks and delete non- dangerous files.
About the maps not working issue: does an error window appear when you enter in them?
If it does, send a screenshot or write what the error says .
Most of the time is because a map is broken and it won't work, but maybe it's just missing files.