I bought the same atlona device for my projector, becuase it was supposed to work with Mac os. But ran into the same issue you guys did.
I have a Mac Pro & MacBook Pro both with 10.6.6, and no desire of rolling back my systems.
I had the thought, since you mentioned that all the devices are based on the same chipsets. Why not try another companies drivers.
I tired the warpia driver on my atlona hd-air and it worked. It is of course a beta, so time will tell how stable it is. But working none the less.
Here is the link:
http://www.warpia.com/support/driver...0a_support.asp
Scroll down to the section titled. "MAC OS X Support for the Warpia PC to TV Products (SWP100, SWP100A):"
You can ignore all the parts about firmware upgrading.
All I did was:
1. Download the driver.
2. install the usb driver first.
3. restart
4. install displaylink driver
5. restart
6. put in the usb dongle and it came up in the wireless usb prefs app.
NOTE: I did not have the dongle in during any part of the install, only after all the software was in and the second restart did I put it in.
Hope this helps.