for the center of gravity see the thread of mine veihicle not moving
someone explained it was because the Model had a defined Center of Mass and the script i attached had a
command called com { 01,02,03} or similar , i removed that and the center of gracity error went
if you dont have a center of mass in your model then the numbers are wrong in the script in relation to the model Y+ is forward Z+ is Up and X+ is Right of (0,0,0) of the Model IIRC
in terms of the axles in a basic model you dont need them so i figured as long as you use simple this addwheel if you use the addweelswing(TBC) you need an array of the axle and an wheel and wheelparameter