OK so after some figuring I now know how this plugin should work.
It must do the following things when mp_tournament is set to 1
set mp_tournament_stopwatch to 1 (default) during waiting for players
as soon as setup round starts mp_tournament_stopwatch must change to 0
somehow enable autoteambalance when mp_tournament is set to 1. I do not know this cvar.
There was a problem with the rounds never ending when I did this, though. I think somehow mp_tournament_stopwatch has to be turned back on towards the end to enable things like mapchooser and have the game go to nextmap when it hits < 5 minutes, but I'm not 100% sure.
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I'm sure there's a plugin for this already, but I searched a while and didn't find anything. I'd like a plugin so I can change the names of RED and BLU in TF2 without having to enable tournament mode.
Help would be excellent.
Alternatively, could there be a plugin that turns ALL cvars of mp_tournament OFF except the ability to change team names?