1. It starts up normally, with the console showing up for a second or 2 and then it switches to fullscreen. No error messages besides "taquake3.exe has stopped working" from windows itself. Note that it can't even get to the main menu.
2. Not sure what you mean by loading it through the Q3A game, but I assume I'm using a stand alone .exe, seeing as it has it's on separate directory in the steamapps folder.
3. I'm using no patch, it's a demo and regular Arena works like a charm. I tried looking around for a patch for Team Arena, but I wasn't sure what to download.
I am also running on Windows 10, could that be an issue?