Since this plug-in hasn't crashed Planet Mofo for months now since I originally got it working, I'll share it here. The plug-in is simple, it all allows you to switch a player's team without having them rejoin. There are different options, like balance on cap, balance after X seconds, etc. The README describes them all. This plug-in is hack-ish as it does bypass the API. License is BSD like all my other plug-ins.
Plug-in GitHub Page
https://github.com/allejo/autoTeamBalance
READ ME!!!!
https://github.com/allejo/autoTeamBalan ... E.markdown
Most Up to Date Plug-in:
https://github.com/allejo/autoTeamBalan ... alance.cpp
Please read the 'README,' it'll answer all your questions. I'm not providing any .so or .dll files because everyone who's hosting should be able to compile themselves. Enjoy. Credit for the original team swapping code goes to Murielle.
Note: This plug-in will probably not work on a Windows server. Not that any real host uses Windows for hosting bzfs but yea... Just as a warning.