So, I updated last night to BB2018 build 520. As midi input driver I have LPK25, which is an Akai LPK25 mini midi controller, however, that is out of the BB equation since I created the midi file with its custom software. The output driver is Microsoft GS Wavetable,and the Sybth is Coyote Wave table DXi. When I play the MGU file in BAIB, then Use VST/DXi Synth must be unticked, otherwise there is no sound from the track. When I save the file to MP3 or WAV, BB insists that the Vst box be ticked.
I tried exporting the song as audio, but it makes no difference. Exporting the song in track actions > save track as Wav, saves the melody, but with piano, not with Harmonica which it plays correctly in the mgu file.
In short, the MGU file is perfect and all I want to do is save it to an audio file, that should not be so difficult.