Alright, I finally found time to open up the door. Here's what I've got...
I removed the vacuum actuator and swapped the wire harness with the one that goes to the handle/lock mechanism. The result is that the actuator now works as it should (as in I can lock all doors from inside the car), but the key will now only lock the drivers side door (mechanically.) Logically the problem must be with the wire harness. I do not have a multimeter with me, but I assume that I'll need to trace the harness back anyway.
Does it matter which one goes where (lock mechanism, actuator...??) The one that doesn't seem to work has yellow/green wires, the one that does has red/blue wires.
Hopefully someone can answer this soon before I tear up the whole car tracing this wire harness
thanks
justin