yes.. but you made many mistakes xD
I just made example codes..
The saving code needs to be set before loading a new level.. not after killing something.
after level_load, you need to set a wait of 2 frames.
for ent_remove, you need to make a loop, including ent_next to scan all entities of the level, and ask for their id.
try replacing your ent_remove with this:
for(you = ent_next(NULL); you; you = ent_next(you))
if(killed_e[you._ENEMY_ID] == 1) // scan for ids and for the stat
{
ent_remove(you);
}
}
Be careful.. the array (killed_e) needs to be big enough to store ALL Level Entities.
When there are 3000 Enemies on your greatest map.. the killed_e needs to be
var killed_e[3001]; //global
to be sure theres enough space for the ids.