In general, game crashes at track loading screen when files are missing (game did not find a file called in CAS/HDC/CAR) : are you sure that mods you have installed are standalone ? Many mods require other mods to work (not present due to lack of permissions from authors).
So from cars that give CTD :
- Open each .CAR file with notepad and check that hdc/cas/aud are present in your car team folder
- Open each .CAS file and check that all .GTL/.GTR files are present in your car team folder
- Open each .HDC file and check that tyre brand (.tyr), damage file (.dmg), suspension file (.sp), gearbox file (.grb) and engine file (NORMAL=/RESTRICTORPLATE= should match .eng file name) are present.
Sometimes mods are not optimized and work only if you set your graphics on max settings (high detailed cars/wheels should be checked).
If all files called are present then check your circuit files : can you launch the trach with stock/default cars ?
If not then open .TRK file with notepad and check that all .GTL/.GTR files called are present in your locations folder (track name folder or SHARED folder).
Did you have modify a file ? You may have introduced an error by modifying a name which doesn't exist. Re-install the mods from archives without modification and try to load cars again.
It is rare but sometimes there are material conflicts between different mods : these conflicts give either bad mapping (different cars use same maps name) or CTD
Voila, cannot say much, you have to investigate mr Columbo