How dare you doubt me! Well if you think about it, you'll notice that most arcade command-lines include the [ROM] parameter which is the rom without the extension. In the map file you're including the extension which would be the [ROMFILE] parameter. If you test this from the command-line of most arcade emulators, you'll notice that it does not work. GameEx will pass everything to the left of the string whether it be the pipeline (|) or quotes ("") to the command-line. So you have to make sure that it's passing correctly.