I contacted Apple because I am not able to create any guest Network on my Airport Extreme because I was told that my modem needs to be simple. Per Apple: "The Guest Network feature will not operate correctly unless your "main" AirPort Extreme is connected to asimple modem........not a modem/router (such as the Actiontec MI424WR Rev.1) or gateway type of device that is often furnished by Internet Service Providers to their customers."
So is it possible to make this version of Actiontec a simple modem. Is this even possible or will I need a new modem?
NOTE: I disabled the wireless functionality of the actiontec.
Do you have FiOS TV ? You can completely bridge the ActionTec or take it out of the equation entirely if you don't have TV to worry about. Or, you can make the Apple router your primary and put the ActionTec behind it, with the trade-off that things like Remote DVR and Caller ID on TV won't work the best.