I recently created a model and imported into GTA IV using OpenIV and came across a problem i haven't had before. Some doors are missing and all of the wheels. Also, what I think is the doors is really bug and blocking my view. Is it the model, something I added, ZModeler, the hierarchy, please help. Actually, every time I start the game and spawn the car again, something else disappears. 

The files that have the option to download are more pictures, ingame and in ZModeler.

GTAIV 2014-08-27 21-59-01-00.bmp

GTAIV 2014-08-27 21-59-04-93.bmp

GTAIV 2014-08-27 21-59-08-82.bmp

GTAIV 2014-08-27 21-59-11-73.bmp

GTAIV 2014-08-27 21-59-13-71.bmp

GTAIV 2014-08-27 21-59-20-25.bmp

GTAIV 2014-08-27 21-59-22-82.bmp

GTAIV 2014-08-27 21-59-25-37.bmp

ZModeler2 2014-08-27 22-02-21-33.bmp

ZModeler2 2014-08-27 22-02-28-09.bmp

The problem is you have things checked that shouldn't be checked. Basically you should only have the L0's checked. You need to uncheck the L1's and COL's. For the wheels specifically the only things that need to be checked is wheel_lf, [wheelmesh_lf]. wheel_lr, wheel_rr, wheel_rf. You should not have the Collisions checked. This is just based on looking at your hierarchy