I think Game-Panel is designed to be installed on a completely fresh server, we tried implementing it out of courtousy for 1 our customers which already have FTP server etc so it might of confused it a little.
Also another feature I didn't like was the 'clan name' as an ID for each server, usually we go off by box and port number, but it wouldn't let us create 2 ID's of the same which kind of ruined our system.
Just my experiences, a lot of people use it - so mgiht be just me

Very picky he he.
Cheers
Ryan