Thank you all for helping a lot, I did it all and more, and it is pretty much same stuff. Though I haven't tried to addapting whole other mod as placeholder and then changing bits, but i think it is little different from how it is now. I wonder could deformable tires be a problem or something, ps I haven't checked yet if the GT40 mod has tires flexing. And I have got some better insight into issue. Seems like game doesn't crash now as i disabled the FFB, or perhaps other things helped. But the issue remains. But now I am able to call a replay right at the beginning and check whats happening and how car looks. First of all car is for some reason turned 90degs to the left, and next issue is that it has no TIRE, SPINDLE, DEBRIS objects on it. I have also opened .veh file with 3Dsim and it opens model nicely. The Y axis is pointing left, and should be pointing backwards. Perhaps if i will rotate the car or change axis on export it will work, have to try it now. I am also renaming a lot of objects, for example lf_TIRE to tire_lf and so on... EDIT: GOT IT !!!! it was mostly naming issue I think. Fixed names and axis and have it in game.