Im not sure if this is the same thing.

My drivers side door lock wont go down unless I press it down and wont go back up unless I use the key or pull it up, the central locking wont budge it. Is it time replace the motor?

Also I have a cheetah alarm/immobiliser installed, will I need to do anything special with the wiring or anything if I change over the motor? Extra wires or antyhing?

Hope you can help.

Most alarms wuld be installed using the existing wiring, so you'd probaly be safe just swapping the motor.