Bluntly: I wanted to create a rescue quest where you had to save someone (in this instance a custom DB Assassin) from jail.

I...

created the actor, ready to be placed (easy)

made the note from Cicero to be delivered via courier (a bit harder, but whatever)

What I CAN'T seem to figure out, is how to set the objective to 'unlock this door = quest completed' and for said assassin to travel to the Dawnstar Sanctuary afterwards.

Maybe I'm just tired, but now I'm tired AND pissed because CK keeps crashing every thirty minutes or so

Help would be appreciated fellow Creators and if I've placed this in the wrong... erm place, sorry.

You would do this through quest stages; particularly ticking the end stage/quest box (whatever its called);

on top of that you can use a script fragment or in the objectives panel to end the quest with a screen note.

http://www.creationkit.com/index.php?title=SetObjectiveCompleted_-_Quest