Here's a picture:
http://www22.verizon.com/residentialhelp/highspeed/networking/setup/versalink7500/121833.htm
basically it has 4 Ethernet ports, not a WAN port
But the way I'm using it is as follows. From Comcast Modem (Lynksys CM 100) I run a cat5 cable from its only Ethernet port to a NIC card in my Main Computer running win7x64.
A second NIC card in the Main Computer (win7x64) I ran a cat5 cable to the Westell-A90-7500 Router. Then I run ICS in the main computer so that any other computer connected to an Ethernet port in the Westell-A90-7500 Router it gets Internet Access.
Everything is working great that way, I have another 3 other computers that connect to the Westell-A90-7500 and they can access the Internet and use File Sharing and Remote desktop connection.
But, I decided to provide some more security to the Main Computer (win7x64) and installed a program called HOTSPOT SHIELD and after Installing it took control of the Internet connection and the Main Computer (win7x64) Internet Connection Sharing (ICS) does not work any longer, but File Sharing and Remote access still works with the other computers connected to Westell-A90-7500 Router.
So after investigating I found out that If I could clone the Mac address of the Main Computer with the Westell Router I could plug directly the comcast lynksys cm100 Router cat5 cable directly to one of the 4 Ethernet ports in the Westell Router and that way I could still use HOTSPOT SHIELD, and use Internet on all other computers connected to Westell Router.
But I got stopped by the possible fact that the Westell Router has not an option anywhere to clone the mac address.
Hope this make sense, at the end I will probably have to do what you suggested and get a different router, DSL or cable-modem that has this option to clone mac address to the Main computer.
Any other suggestion it's welcomed.