Ok I think I actually found the issue. Even though I used the exact named emulator you listed in the ReadMe, there appears to be a rom floating around with that file name that either has some kind of issue or is just a different rom with the same name. I hunted a little deeper into the net and found a different download site with the same named FireRed Squirrel rom than the one I initially found, and now it's working just fine. So I don't know, I'm going to just assume that that's what's going on.