Saturday I took the body to the SEALUG meeting (Seattle Lego Users Group), and it fell apart in the car when I braked for a stop sign. Internally there's some hidden hinges that didn't really have a ton of surface area. We cleaned up some to make the body sturdier. Now the hinges connect to the body panels with nearly 3 times the surface area. It might still need some glue to be motorized, but it should at least not fall apart.
The front vents weren't done earlier because the hole in the front panel needed to move a little from the original plans. Additionally, LDD let us have some error in the brick attachments that didn't work in the real world. It took quite a bit of effort to get the panels securely attached. At one point there was a quarter-plate difference in height between the vents and the hole to attach them. I have no clue how to move something 1/4 plate, and it was too loose as it was. I fixed it by making the middle blue stripe slightly wider, it was a single stud (2.5 plates), now it's 3 plates. I also noticed a few missing outline tiles.