I believe you will not need your USB DMX Dongle anymore as the Active Hub will output DMX. I haven't built the whole system yet, so someone please correct me if I am wrong, but the way I understand how the Active Hub works is if you put the blue shunt connector in the #1 position on the jumper labeled "DMX Universe," the first 512 channels you program will be sent to the "DMX Output" port on the hub. So you can connect Expresses, Aethers, other DMX equipment, etc to this output and it will work as normal. Channel 513 on will be sent to the Smart String Outputs.
You can also change the firmware on the EtherDongle and use it as a DMX dongle that takes input from your ethernet port vice using USB. This is what I did to test my EtherDongle since I don't have the rest of the system built.
I don't think there is a Wiki for all this. It's mostly stuff I remember reading from the posts and such. I've been keeping a running log of info to try and keep things straight in my head. I might formalize it a bit and post it later. My small attempt to give back to the community that has helped me a ton.
Aloha
Nathan