help on spawning mobs in a instance

[gave012]

hi everyone. i just want to ask how to spawn mobs on a instance i followed the wiki and the instance is working but it cant spawn mobs why is that happening well here my script and hope someone can help me XD

my details on instance.db

4,Hades Labyrinth,5400,casp_fild01,173,40,casp_fild01,casp_fild02,casp_cave,casp_dun01,casp_dun02,haunt_e,1@haunt,haunt_h

and heres my script.

prontera,150,150,0	script	Instance	100,{

    .@mdName$ = "Hades Labyrinth";
    
    mes "[Guard]";
    mes "How can I help you?";
    switch(select("Create Instance:Enter Instance:Destroy Instance")) {
        
        next;
case 1:
	if (instance_create(.@mdName$) < 0) {
	mes "^0000ff" + .@mdName$ + "^000000 cannot be opened now.";
	close;
	}
	mes "[Guard]";
	mes "I will open up the tunnel to ^0000ff" + .@mdName$ + "^000000.";
	mes "I wish you good luck.";
	close;
 
case 2:
	if (instance_enter(.@mdName$)) {
	mes "[Guard]";
	mes "There has been a problem with entering the instance.";
	close;
}
end;  
case 3:
	instance_destroy();
	mes "[Guard]";
	mes "The instance has been destroyed.";
	close;
    }
	end;

OnInstanceInit:
	enablenpc instance_npcname(strnpcinfo(0));
	end;
	monster instance_mapname("casp_fild01"),0,0,"Poring",1002,100,instance_npcname(strnpcinfo(0))+"::OnMyMobDead";
	end;

	
	OnMyMobDead:
		dispbottom "Fuck You!! You Killed My lovely PORINGS!!";
		end;

}

i hope that someone can help me with this getting frustrated.

thats only a test instance so that ideas can follow trough but i am stocked with spawning mobs.

bump.. someone help please..

bump any help please? thanks in advance..