Check your gateway setting on the groov - It will need to know how to route packets from the 192.168.7.0 network to the 192.168.8.0 network. You need to put the gateway for the 192.168.7.0 network as the groov gateway.
Hopefully your plant network does not require routing to other networks, as the groov only supports a single gateway and there is no ability to enter static routes.
