Well, let me put it straight:
I18 Mids builds will load perfectly fine in I19 Mids. It'll take a bit of work between Energy Aura, DeProgrammer, and myself, but even if it means that I19 Mids will be late, that's what'll happen. High priority for me.
Mids builds saved with the unofficial patch have no guarantees. I'll look into it, but it might not work.