Hi!

Here's the beginning of your physics:
Read all about the "phent_..."-methods in your handbook.

Code:

---

entity* crate;
 
function main {

        level_load("your level with a simple hollow-cube around the origin");
        wait(3);
 
	crate=ent_create("crate.mdl",nullvector,null);
	phent_settype( crate, PH_RIGID, PH_BOX );
	phent_setmass ( create, 10, PH_BOX );
	phent_setfriction ( crate, 1 );
	phent_setelasticity( crate , 2, 2);
        ph_setgravity ( vector(0,0,-368) );
 
        while(1){
          wait(1);
        }
}

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