How do you do map caches for multi map rpg's

Is there a tutorial anywhere that explains how to do this? Or can anyone else explain how it's done?

Simular to the Frozen Throne Orc Campaign...

How do you make map caches that remove items you've already aquired on the map... Change the entrance location, so if you come back to the map from an adjacent map, the starting location adjusts properly.
Save dead bosses, Events that have played out and finished quests.

I've not been messing around with that kind of cache use lately, but I guess by saving lots of booleans into the game cache and then checking them with Ifs.

Here is a tutorial I posted, but not wrote, on game caches.

Cache Tutorial

Thats a very vague tutorial that only covers the basic cacheing features.

Blizzard actually saves the map and reloads it when you return. That way nearly all things are kept as is. The game cache is then used to apply changes to that map resulting from the other maps that have been played in the meantime.
I suggest you have a look at their triggers to see how exactly they did it.