Code:

---

action level_12 
{ 
	my.enable_impact = on; 
	my.event = change_levels_12(); 
} 
 
function change_levels_12() 
{ 
	wait (1);
	if (you != player) {return;} 
	Load_level (M2.wmb); 
	sleep (1); 
} 

---

Those shouldn't be there...

and it should be "M2.wmb" - remember the quotes