Thanks for your reply. I have now installed the .NET stuff and the player now opens on the PDA.
However it tries to autodetect the Gps (a Garmin XT10) and after some time comes back with the message
[Error starting the Gps. Check the settings. No Gps device could be found matching the requested "NMEA-0183" protocol]
I am now totally lost!
btw: the Gps is detected by the Garmin mobile XT software running on the same device.