Track download does nothing


I am just making my first steps with bt747 with my photoMate 887 Lite. The COM connection is successful established and I see the GPS position in the info box and on the map. However FlashInfo, Model and FirmWare remain in unknown state.

If I now try to download the tracks nothing happens. I changed the way BT747 is started so that I can see the log messages from java.exe on the terminal, however nothing (no Exception or similar) is printed out there.

How to find out what is going wrong?

Environment Win7 + Java 8 64bit.