Python 3.5; Cannot find BlenderVR root

[Cygn]

I'm on fedora 24 which comes with Python 3.5, so PySide is not available (and won't be for python >3.4, see pyside/PySide#132)
So I try to run without the gui. here is my cln:
./blendervr start -configuration ../samples/basic.xml -screen 'Fullscreen' -processor "../samples/basic/head-navigation/roomVR.processor.py" -blend "../samples/basic/head-navigation/roomVR.blend"
see complete output [here] (https://gist.github.com/Cygn/daba136bcab1db8ed9acb52f744712ff)

I guess PySide errors are harmless, and the daemon starts, but dies with:

AttributeError:
'NoneType' object has no attribute 'useLoader'
Cannot find BlenderVR root !
Try adding --BlenderVR-root option to BlenderVR (./blendervr --BlenderVR-root="path") !

Adding different flavors of --BlenderVR-root pointing to source, . or /absolute/to/source didn't help.
note that above processor/xml/blend configuration were tested OK.
I guess there are other modules which won't take 3.5 ? Is there a workaround ?

[Cygn]

By the w&ay this is not related tp Py3.5.
It's the gui-less mode which cuases the issue.