How long did you drive under open sky? It may take a couple of minutes if the unit has no idea where you are. Also, a broken GPS antenna should cause an error code when you check the RNS-D with VAG-COM.
The problem occured in two different places where I put the antenna. When the antenna was first installed it was installed it in the center on the dash. I did move it around a little and this is when I noticed the problem, so after I took it back I had them put it behind the steering wheel. ( I used one of the pictures from the quicklinks installs for the position and placement of the antenna.) And it made no difference.Have they installed the antenna the correct way round? - i.e. with the sensitive side pointing upwards (not down or to the side).