Quote: "If its an old map you've made a standalone of in the preview version, then it might be the light map,"
Belidos is right ... Of course That makes perfect sense , Removing the light mapping and re doing it would probably rectify the situation. I have had similar weird things on old maps caused buy old light mapping ( Not exactly That ) but definite model issues
I wouldn't re light map in DX11 yet its just not working correctly
The only person ever to get all his work done by "Friday" was Robinson Crusoe..