Very odd...
The p3d file is the model itself and all the data that goes with it...
If this problem continues I would open up your DTA folder, and download the PBO tool from here.
Extract the data3d PBO and delete the budova4e file
if that does not work, take all your important items out of OFP, and re-install the game, and test to see if it works then.
If it does, place all your important files back in, 1 by one testing to see what file is causing the trouble.
Otherwise just re-install and problem solved.