I've seen this happening on another computer, I'm pretty sure it's actually a related problem. Apparently the way I've been doing quick 2D rendering isn't actually possible on newer hardware without artifacting so I'm going to have to refactor my system for that slightly. For now I'm uploading some different shaders that should work better (albeit at 1/8th the speed), should be done in about half an hour.
As for illegal hardware instruction errors, that would be from the instruction set I've compiled with, CPUs made before 2011 are pretty much guaranteed to not work. Frankly this is something I'm open to spending time on as I would like older hardware to be able to run the game, it's just hard to find a good set of compiler flags to build with.
EDIT: Also the game is 64-bit only, I could build for 32 bit as well but I haven't tried up to this point. I might make a point of that for next Demo Day.