Ok, I've given it a try and I can export with no issues, this is how it looks in game right now.
At the moment you've still work to do.
- the window where the door used to be needs to be sealed up.
- the body boxes are missing, see this thread for details as they have changed since the tutorials were made automationgame.com/phpBB3/viewtopic.php?f=38&t=8095
- You need to add and define some working morphs.
- The LUA file needs to be set up with the right material assignments, you wont know what these are till after the export, 3dsmax has a habit of moving these :S
you may also want to consider re-doing the uv map to make it less obvious there used to be rear doors.
I've also attached the kjc files just in case you still can't export and would like to see your mod 1st hand
export.zip (456 KB)