So there is some problem with running my games on the actual final version of the PyBadge — the display goes white randomly several seconds after starting the game. If you have stumbled into that, don't worry, it's not you, it's me.
The bad news is that it's very hard to debug without actually having a unit that exhibits the problem — it all works perfectly fine on the prototype I have. There has been some changes to pins, in particular the TFT_RST pin was swapped with the TFT_LITE pin internally, but that should be handled by the firmware. I'm still trying to figure out what is happening there.