I know some of you guys use only models as parts of your levels. I was thinking about switching over to this method but I am not sure what I need to do; what flags do I have to set and what variables do I have to change for the physics to work correctly? Apresh...

to get psyschics working, I think you need to add level geometry under the models. I think so at least what I've heard and seen..

as inestical said, use invisible blocks for things like physics/newton. make the models passable and it should work. you have to put blocks at the boundaries with the invisible flag and do all grafics with the models.

you can also use the models as ground if you dont need physics with the new trace USE_POLYGON mode.

how can i use this use_polygon mode??

Actually you don't need level blocks for physics to work. The simulator I'm making is entirely models and terrains, and the vehicle uses the template physics code. I also have a level that is strictly models. Just be sure to set the enable flag on for whatever surface your player is on.