Hello,
Thanks for taking some time to answer me. I've just take a look at the wiki page you indicated but i'm totally noob and don't understand (unfortunately) what they means on this page.
I know for having trying it that Singularity viewer handle without problems the space navigator (the big problem i have with this viewer is that it refuse to stream music-yours having not this problem).
one of my only hope is now to try to found the code in singularity and (if it's not forbidden) add it to your viewer (and i wonder also if it's possible to realise it-perhaps there is incompatibilities between cool_vl_viewer an singularity).
But well....Hope isn't forbidden