If the alarm has been fitted properly it is impossible to get locked out of the car. On the Z the 2 doors and the boot can all be connected using 1 wire, (red and white behind the clocks) If only one door has been connected to the alarm then it won`t work properly. The Toad Alarms won`t lock the doors if a door is open(that feature is on a 12 second timer) so if it is locking with a door open then the alarm isn`t seeing the door that`s open.
Easiest way to check, open 1 door and set the alarm, if you get 3 bleeps from the siren then that circuit is working, try the other door, boot and bonnet seperate. If you don`t get a fault code when arming then that circuit isn`t working properly.
Bob