I can confirm that this app works to tether over wifi on the Design, without paying the $10 a month.
My phone is rooted not using any of the methods here, I will try to post an tutorial on this forum later, however, I did unlock the bootloader first.
Also, you must set the device to the HTC amaze. (Generic ICS seems to work, but i could not load any webpages)
The connection (not in 4G) was good enough to video on skype!!!!