It feels like I've tried everything at this point - I've been hitting the nostalgia wall hard for hours today, trying to get the game to run at 2560x1440P in a borderless window (to allow for Alt Tabbing)

"Stock" the game will let me alt enter to a window, but it forgets it the next time I launch it.

Using the ureschanger doesn't seem to work at ALL, changing nothing ingame (the resolution is clearly still stock, even though I've set it to 1440P)

Running ureschanger (with either windowed 1/1) and trying to turn it into a window, makes the game crash immediately, so Borderless tool is pointless.

Does anyone know what is up here? I've been reading guide after guide and these steps are supposed to work.