Try this one.

Code:
///////////////////////////////
#include <acknex.h>
#include <default.c>
///////////////////////////////

void Go()
{
	error("hey!");
}

action Fly()
{	
	set (my, PASSABLE);
	my.skill15 = (void*)Go;
}

void main()
{
	fps_max = 60;
	level_load(NULL);
	ent_create(CUBE_MDL, nullvector, Fly);
	
	ENTITY* ent = NULL;
	you = ent_next(NULL);
	while (you) 
	{ 
		if(you)
		{
			ent= you;
			break;
		}
		
		you = ent_next(you); 
	}

	if(ent)
	{
		void act();
	
		act = (void*)ent.skill15;
		act();
	}
}



i think you are using A7? because felix's code work with A8.