which settlements do you have selected for pre-building, I found that if zamoja, Jamaica plain & kingsport have vanilla enemies still in them & seem to cause this exit freeze, as with them included the freeze happens, without them selected for pre-build no freeze.Same issue here. The only difference being that the freeze only happens once I take my first settlement (for me that's Sanctuary). I do have Sanctuary removed from the settlement pre-build list. There are only 2 settlers to deal with during the raid.
Any attempt after that point to Save/Exit to Desktop results in the game freezing. I have let the game even run several hours in the hopes it might sort itself out, but with no lu