97 Zetec Ghia Central Locking And Idle Issues!!

Hey peeps, Daughter got a 97 1.4 Zetec Ghia the other week, Since getting it it has developed a couple of gremlins and was woundering if any one could help as it was a private sale so no dealer back up,.

Central Locking--

-Occasionaly when you go to unlock with the key the system just cycles through lock and unlock, I have not been able to open the Drivers door during this However I have managed to open the front passengers door and then lock the drivers door on the interior handle ( not tried it on the passengers) This seems to stop it and unlock all the door, Ive had a look and both front door locks move the same and the rear two move the same with the rear door handles going in a further 5mm than the front. Any one got any ideas,

- Only got one key with the car ( the owner thought she had lost them but has now found them so is sending them on) Thought the battery had died in it so changed it and followed the destruction in the paynes manual which said turn the ignition to XX then back and hold this button then when it flashes hold this button , Any ways did that but it did not work. The light on the clock just did its normal flash that it does. Any one got any advice on this, Do I have to use the MASTER key on the ignition then do the button bit with the dead key or some thing ???

Idle--

Have noticed that if you start her up and let her idle whilst you do bits n bobs she some times dies after a minute. Is this normal or could it be something to look into the car has very low milage 54200 and was only used to drive round the village and to the MOT centre.

Security--

What class would the factory security be as the insurance has put down thatcham one which im not too sure it is.

Cheers peeps