It took a few hours and it's now approaching 7 AM but I think my FALSE interpreter written in MUF works.
It's missing a few commands I want it to have, but I think I'm going to call it a day and finally sleep. I'm really pleased with myself because I can run FALSE programs anywhere on SpinDizzy.
Only problem is trying to calculate primes with it easily chews through the ~20,000 instruction limit my MUF programs get, but that's expected. :p
I implemented all three of those and updated the pastebin link.