Put the goomba emulator in the root of your CF/SD card and make sure it is named goomba.gba now stick your .gb roms anywhere on the card, load the GBA<P and choose the rom you want to play, or if that won't work, just load the goomba.gba file, then find the rom you want to play.
Great, the games are working. Thanks a lot, man. I probably shouldn't ask you this after what you've done for me but is there any way to play .gba roms with GBA Movie Player.
Not as far as I know, the problem is the RAM limit of the GBA, the GBAMP can only use files that fit into the RAM of the GBA, or that have been specially coded to work stright from the card.