Can't get Time Machine to work with Nighthawk

I completed all steps through 5.a. For me, the only way I can access the two USB hard disks plugged into the router is to go to the Finder, choose "Connect to Server..." (which is command-K), type "smb://routerlogin.net", enter my username and password, and then click the disks to mount them. One disk has the TimeMachine.dmg on it. When I double-click this to open it, I get an error: "The following disk images couldn't be opened", and it lists TimeMachine.dmg and reason is "Input/output error". I've tried to open TimeMachine.dmg via Disk Utility, verifying it there, but neither will work.

Oh, and I've spent about 90 minutes on hold and getting transferred and hung up on when I've called Netgear several times over the past three days. The four people with whom I spoke each told me they needed to get me to the next specialist who could handle my issue. Some of them didn't know what Time Machine was.

Any help will be seriously appreciated.