Quote: "I had a little breakthrough myself over the weekend. That Chinook model is made of lots of separate meshes by default (the hull, propellers, seats etc.) but when I merged them all together into a single mesh and exported, I didn't get the rotating problem."
That kind of goes back to what i was saying earlier, it sounds like the global rotation wasn't zeroed before the model was exported. GameGuru really doesn't like non-zeroed rotation on models, it tries to zero it itself, which causes this sort of thing to happen. What modelling program are you using?
Quote: "Having said that, the interior of the Chinook (yes, it has an interior) now exhibits some slight lightmapping artefacts. Check out the seats (because the Chinook is tipped on its side, they are on the 'floor') in this pic and how they have weird highlights. "
That might possibly be the thickness of your geometry. GameGurus lightmapper needs all "walls" opposing faces to be a minimum of 5 to 10 units thick to register as solid for the light mapper, anything thinner will cause sunlight and shadows from sunlight to project beyond the "wall", and will cause other weird artifacts..
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