We installed WP Super Cache on a site, and didn't follow the instructions carefully enough. Things got really messed up, so we deactivated and deleted it, but since then the site has been acting really strangely. We deleted the cache directories, the plugin files, and some other stuff, but I'm wondering if there's anything else that needs to be done in order to ensure it's been totally removed. Does it add stuff to the databases? Is there anything else we need to do to make sure it's really not there? Any advice?