So, I've been playing a bit with MKS but also with, drum roll please, Interstellar Extended. Yeah, so, I've discovered that both of these are perfectly fine working together in almost everything except reactors... the main thing powering my bases. I've tracked down the problem, I'm fairly certain what needs to be done to fix it, I just can't do the fix myself.
Basically, the reactors have decided they want to use UF4 as their fuel (as opposed to enriched uranium) most likely due to an override by IE. However, IE has conveniently decided NOT to override the actual refueling mechanism, which means I can't refuel my reactors (I'll explain why mks can't refuel them either in a sec). So, you'll tell me, just disable the IE override, and to that I say, I'd love to. However, this reduced the output of the reactors to the point that every single base I've made can no longer power itself. So I'm stuck in a dead end.
The solution was to incorporate UF4 transfer into the mks fieldrepair system myself. I thought I'd succeeded until I looked into the actual code for the field repair module (on the github). It turns out that nothing I do will allow this to work because the cs file for the module doesn't actually include UF4 and I don't know how to edit the cs file from my install (if that is even possible).
So here is the question: Is there ANYTHING I can do to allow field repair to also refill UF4 on my side? Thanks for the help, this is bringing me to my wits' end.