Demul Won't Run Naomi

[YeshyYeshiam]

Hey guys, I'm pretty new to all of this emulation stuff and I downloaded the Demul emulator to play Monkey Ball and a couple other games. I set up all of the BIOS and controller ports when I first ran Demul.exe. I directed Demul to the 'monkey_ball' ROM folder and clicked OK. I then did File>Run Naomi and found the game (GDS-008). When I ran it, it came up with the error "Unable to find 'epr-21578d.bin' in romset 'naomi'.

Any ideas on how I could fix this?

 

[ReyVGM]

You're missing a rom. google it.