This could be a bit of a longshot, but thought I’d ask…
I’ve recently discovered some romhacks/homebrew for N64 listed here: https://n64squid.com/
For some of these, you have to compile them from source (such as Wolfenstein 64, Commander Keen, and Five Nights at Freddy’s), so I decided to give it a whirl! I installed WSL for my Windows PC, installed Docker, and got libdragon installed. The first port I compiled was Five Nights at Freddy’s via the instructions here: https://m.youtube.com/watch?v=cSOmlyvK9gQ
I successfully built it and the game booted and runs on my actual N64, but it wouldn’t run on the MiSTer core. I also built a rom for Spear of Destiny ( https://n64squid.com/wolfenstein-64/) and saw the same behavior: it runs on real hardware, but not on the core 
So, I was luckily able to obtain a different copy of the Five Nights at Freddy’s rom and lo and behold that copy works on both real hardware AND the core! I also obtained a copy of the full version of Wolfenstein 3-D (I couldn’t find a pre-built rom for Spear of Destiny) and that worked on the core as well. So it definitely seems like there is something wrong with my build process.
My question is: Are any of you guys familiar with doing this and could do some testing for me by building a copy of the Spear of Destiny rom and see if it works on the core for you? I would love to see if someone can get it to work and maybe help me
retrace your steps so I can figure out what I might have done incorrectly.
Thanks for anyone that read this or can offer help!!