If I use any kind of code! For example ninja code from AUM or Zelda code.
I think problem is in here
vec_set(temp,my.x);
temp.z -= 4000; // calculate a position 4000 quants below the player
trace_mode = ignore_me+ignore_sprites+ignore_passable+ignore_models+use_box;
result = trace(my.x,temp);// subtract vertical distance to ground
my.z -= result;
but I can not fix it frown
About model, take for example this model
http://rapidshare.com/files/182799375/MODEL.mdl.html