Astra 777 in a 1996 Mustang GT

I have an issue with this alarm. I've hooked up the door lock wires to the control and everytime I use the remote to lock the door, it automatically unlocks itself. I was wondering if I'm suppose to de-activate the factory alarm or if maybe the wires are wrong (which i highly doubt). I thought this should be as simple as adding on the alarm, but it's giving me some trouble, so I thought I'd ask the pro's and see if anyone has any information, or tips for me. Any help would be greatly appreciated.

OH and by the way, i've already looked at the chart that comes up on this site for all the wire colors and functions for my car, and i've searched through the forums to find a topic similar to mine.

Sometimes cars will unlock themselves if they think that you might be locking your keys in the car. Check your key  sense wire on the car. Those things are notorious for going out on fords. I think its a black blue wire at the cylinder.  Does your door buzzer beep when you turn the car off and open the door with out the key in it? If it does, thats a good sign that the key sensor is going out.