No sound from Spectralayers Pro 8 in Cubase Pro 11 with multichannel files


I recently bought a license for Spectralayers Pro 8. I have to QC and restore 6channel audio samples and it would be a big thing for me to being able to to that inside Cubase Pro 11 - that was the main reason for me to jump on Spectralayers.
Now some scaling issues in Hidpi mode under Windows aside, everything works perfectly as expected with stereo files. However with multichannel files (as mentioned 6 channels in this usecase), I don’t get any sound from the file during playback.
I thought about if ARA protocol is somehow limited to cause this behaviour and checked it in Reaper. Indeed I only get a stereo stream in playback, but it downmixes all 6 channels in that stereo stream, so it basically should work to at least hear a stereo mixdown.

Is there anything I’m missing? I’d really want to do these jobs in cubase.

Thanks for your time

(I already posted this topic in a Spectralayers thread and have been told that it is a Cubase issue, as it works within Reaper and SL)