Okay, so another update. I got this to work and wanted to document in case anyone else is doing this. I updated my HyperLaunch and the videomode drop down now includes opengl so I was able to remove my code in the mame.ahk file (which was forcing everything into opengl so the shader would work). Now that it is set up properly, the Rom Settings in the Global Settings Editor work for -video gdi. I absolutely love this shader for games like The Simpsons 4p or X-Men 4p, but it just didn't work with narrow games like Air Gallett. Hopefully this will save someone some time in the future as it was driving me nuts for days.