Help, again... :P

[i3670]

void OnStart()
{

for(int i=1;i<=5;i++){
AddEntityCollideCallback("Coal_"+i+"", "CoalArea", "CoalFunc", false, 1);
}

}

void CoalFunc(string &in asParent, string &in asChild, int alState)
{

AddLocalVarInt("Var_coals", 1);
CoalLocal();

}

void CoalLocal()
{
if(GetLocalVarInt("Var_coals") == 2)
{
SetEntityConnectionStateChangeCallback("LEVERNAME", "func_furnace");
}
}

void func_furnace(string &in asEntity, int alState)
{
if (alState == 1)
{
whatever happends when the lever is pulled and 2 coals are inside
}
}

I think that should work.