Re: Spare key won't work
If your other key turns both the door and ignition locks, but this one does not, then it is not the key for the car. Whether the fob is programmed or not, a matching key will turn the mechanical locks. So either it was cut wrong or someone got hold of a used key and "hoped" it would work. If both operate the mechanical locks, then programming it should work. You may have to replace the internal fob battery for the programming to work.
Not laser cut - ok. Maybe I am thinking of my Audi keys, which somewhere I read were laser cut and look almost identical to the XF keys. The Germans seem to like switchblade key fobs.