the APRS connection is working with the node now, using UI-View32 as the APRS interface.
Also still trying to get reliable DTMF decoding by my current node, I tried different radios, so finally I tried a notebook computer, now it decodes DTMF commands (via thew radio port) just fine, so this confirms the audio from the radio is fine.
The notebook is an old Compaq P3-500 with ESS Maestro audio interface, so this certainly works
better than the audio interface in the Compaq Deskpro P3-1GHZ
currently, its still work in progress.