Sure I do. Many GB DMG units here.
I use a modded cart using a flash memory adapter by JRodrigo and its cart flasher.
Works very good!
Private message me an email address and I'll send you a download link for the ROM file. Would love to get your feedback on the current build before we lock the code & begin building out different dragons based on this core combat experience. Can you send us photos or other market materials of you playing the game on your GB?