MM_Dev_Vincenzo Permanently banned me today because i called him a bad admin. I said it because 1min before he banned someone because he called himself fascist. Vincenzo said "i dont like racists". I got banned from the mm_official battle server.
You can continue playing in the server but you need to modify the registry entrie with the key of the game
but i think that i cant write a detailed tutorial in the official forum, you must experiment with registry entries, but dont uninstall the game because if you uninstall the game entries will be deleted.
i will only give some clues, try searching the registry entries and copy the necessary, uninstall, install (not the steam version) and now you can modify the entries.
another hint, maybe you need copy files from the steam version