Need help with scripts

[NumsefisK]

Hey. I'm new to modding/making custom maps and I was wondering how you make a key match a door and I'm also trying to make the monster spawn when you pick up the key. And when the monster enters the room and checks it, how can I make him walk out after a while and despawn? Does the monster make the sound itself, or do i have to find the sound file too?

And how do you make a note that can be picked up and read by the player?

I heard theres something that has to be done in the .hps file, but isn't there something in Callback in the level editor too?

Edit: typos