It's good to hear that the final version mostly takes care of that - I wonder how this was done, does anyone know?
A Demented Goldfish, this region swapping sounds annoying.
Another mod, Wind from the East, prevents region trading by default. They offer a
sub-mod to allow region trading. Maybe, by looking at that sub-mod with
Pack File Manager, you could work out how to create a sub-mod for DarthMod that would disallow region trading?
Alternatively, you could try editing the DarthMod setting which affect the AI, so AI factions are less likely to want to trade regions. Bran Mac Born, who specialises in modding the AI, suggested
possible ways to do this.