Update 2:
Turns out it a blank key only and I would need the
Key code to have it cut for the X5...bummer

Time to give local dealer a call.

Bit the bullet and.....
Ordered a key from the dealer, will take a day or 2 because of an
afternoon order they will text my mobile/cell when the key is ready
for collection.
Price is just under £39...$66 U.S... it is a metal key and will open the
door the guy said it will also start the engine and if alarmed it would
stop once the engine is started?
All in all seems like a quite a good deal the guy gave me but I will
reserve judgment until I get the key and try it out?

Once again I thank everyone for their input
My very best regards to all !!!

Actually, since the key can start the car...it means that it has the EWS chip. Thus when you unlock the door with the key...the DWA (anti-theft alarm siren system) will be deactivated because it allows for opening with a key (manually) from the door lock cylinder, or with the remote key.

With your new key, it will be just like 2 people with a key to your vehicle...when one LOCKS the vehicle with their key...and the other person comes back and UNLOCKS the vehicle. The alarm doesn't go off. :)

When you get the new key, when you unlock the door, take a look at the DWA status LED below the interior rear view mirror. If it turns off and doesn't blink, then DWA (the alarm) has been deactivated and you shouldn't have to go thru the "emergency alarm disarm" by quickly inserting the key into the ignition. :)

thanks for the info Qsilver7 that`s handy to know,
didn't know about the panic alarm mate
Thanks again

Hope everything works out okay for you. :) Yep...pressing & holding the boot/tailgate release button on the FZV (remote) key will initiate the alarm:

Got the key today but it wont open the door :(
I had a look at the original key lying in the boot/trunk and the grooves
are worn down a hell of a lot compared to the new key.
Absolutely p*ssed off now with this now, I called BMW and they said it looks
like the only way is to retrieve the original key is by "Smashing a window"
I will need to source a window from a scrap yard first before I smash one
as the weather in Scotland is dire at times, in hindsight should have smashed
a window rather than buying a new key now it will be twice the cost.

First, I'd double-check my VIIN (look at the MFG label on the driver's door jamb or other VIN locations: windshield-lower dash, right strut tower in engine bay, behind the rear license plate, etc)...then check the paperwork from the dealer to make sure the correct VIN was used to order the key (mistakes in data entry can happen). There is a reason why some ALPHA characters are NOT used in the last 7 digits (the "serial number" part) of the VINs on vehicles for the USA market (I,O,Q,U,Z for example)...and that's because they can be confused with numerical digits or other alpha characters. :(

Do you have any lubricant or penetrating oil with a small straw that you can insert inito your drivers door lock cylinder? If the lock isn't used manually, it may just need some lubrication.

Also try to methodically work the door lock cylinder...perhaps adjusting the depth of insertion etc.

BTW, is this a right hand or left hand drive X5 (I forget which side of the road they drive on in your country)...but for us LHD folks...the image below shows the electronic & manual lock/unlock positions:

I truly hope it doesn't come to this...but if it does...remember that if you originally locked the vehicle with the key, then came back and unlocked the tailgate to get something, then closed the tailgate...the vehicle is still DOUBLE-LOCKED...and if you smash a window to try & unlock/open a door.....you will need to follow a SPECIFIC procedure that was mentioned previously in this thread (post #11):

1. press the central lock/unlock button on the center console
2. then pull TWICE on one of the door handles

If you don't follow the procedure above, the interior door handles will not operate like normal....and also be prepared for the alarm siren to sound off from two sources...the IMS (interior motion sensor) and//or from the emergency UNLOCK procedure (from the steps mentioned above).

To silence the alarm,you will need to INSERT the key into the ignition and turn it to position 1, 2, or start the engine. The alarm only stops when the key's EWS (individual serial number) is recognized as a valid key.

I think I would rather replace the drivers door lock cylinder myself. I would drill the cylinder out and then get a phillips screw driver to unlock the door cheaper the replacing a window. IMO :)