I also need help with this. I have a game, Ghost of Tsushima through steam that I want to enable HDR for. I used the script above and it works to turn HDR on before the game launches. I get the notifaction that hdr is on and then the game launches and it works perfect. The problem is after I close the game, it does not work to turn if off after the game closes because hdr remains on, I followed the steps to run after main application, I can see the screen colors look washed out. If I run the ahk file outside of launchbox, I can see it working correctly, it turns hdr on and turns hdr off, it just does not work with launchbox.