hyperion.ng 1 usb grabber in 2 instances

Hello,
I gave hyperion.ng a try yesterday and I like it very much. One thing I can't figure out though is how to use one usb grabber in two instances.

I've 2 nanoleaf canvases in two instances but I can't use them simultaneously with my hdmi grabber.

Also, even though the client tells me, that the grabber config is shared between instances, changes to said config in one instance are not shown in the other.

Help would be much appreciated
Thanks in advance
Torsten