If it marks them as interesting they won't be downloaded - it's either autodownload or mark as interesting. Are you trying to auto-download spots? Cause it seems I haven't written that part of the code yet
RSS and Groups should work just fine tho. If not please post a log file of an update while debug level is at DEBUG.
Also note that only _new_ sets are marked or downloaded, so each set is just processed once after an update. After updating preferences all sets are processed and those that haven't been marked / downloaded before are matched against the search terms.