Use MyWi USB Tethering to share Internet with WIFI Router

I am trying to setup the MyWi app on my jb iPhone 4 to share the internet with a seperate Wireless Router. I have a Directv receiver that doesn't have Wireless, but does have ethernet port for internet connectivity. I need to share my iPhone's Internet with it, but am having difficulties so far. I have plugged in the router to my ethernet port on my computer while it is connected to the iPhone internet via usb, and told it to share from iphone usb to ethernet, but it doesn't seem to work. My MAC keeps trying to connect to the wireless network my router is broadcasting instead of sharing the internet. Any ideas?