Secondly, here's something I can't take any credit for, but I want to share it. So if you see "Zadrave" and "Gamemaster1379", give them a round of applause. It's a little config file tweak that lets you enable Pyrovision support on any map! (For some reason, by default Valve only added support for a few maps)
http://pastebin.com/3aM4KgeQ
Save that into your cfg folder as mtp.cfg and bam, all of the maps included in TF2 now support Pyrovision to some extent. If you read that file, you should find it pretty easy to add support for custom maps you like, too. It's all clientside, so go hog-wild!
Si sur toutes les maps si tu veux. I_I