So I figured out a way around my 8 device limitation...
Go under add device, then z-wave generic... the luup blue bar comes up telling me to add a device. I F5 the screen which takes me back to devices, then go back into add device and now select generic ZigBee. Then ctrl+F5, device should now show up ready to configure... if it doesn't, reload luup.
if this does not work and you have access to a zwave device that always fails to configure (I have some crappy window sensors that never worked right), you can add a new zwave device then select retry to remove the node, after removing the node and attempting to repair it, vera will be unable to configure the crappy device (I think they are enerwave or something)... this causes the vera to keep open the "add a device" in luup - just follow the steps you would to add a generic ZigBee and it will add.
I also added two Iris-branded Centralite 3210-L binary devices from Lowe's (you have to change it to binary light after initial addition as it will first show up as a dimmer). Prior to adding these two ZigBee (and zwave) repeaters, I would have half of my smart vents drop off the network. They seem to have improved the responsiveness of the mesh.
If I continue to face dropouts I will probably create a scene to periodically close then open the problematic vents or possibly add another two ZigBee repeaters to the network.
