XB8 MAC filtering question

Is anyone having success with doing MAC Filtering with the mode set to "ALL" on the XB8? I replaced my Arris owned router with the XB8 and I am having very little success in using the filtering option. It appears management of this XB8 is either somewhat limited, or somewhat restricted. I have the MAC addresses set propertly ( used them for six years on Arris), and when I set the mode to "ALLOW ALL" of course all units will connect. When set to "ALLOW" I have three older devices that need to run on 2.4MHz and use WPA2 security and these devices will not connect even after I have changed the security to WPA2.

I tried to set up Parent Controls to turn on advanced security from the XFI app, and it will not turn on. The app just goes between two pages stating it is not on and gives me options to turn it on, however, it just gets stuck in a cycle between the two pages of the app. Support tried to figure it out with no luck. 

I tried to split out the two frequencies and when I try to put the MAC addresses in the 5 MHZ frequency and then save them, the screen refreshes after the save but doesn't show the added addresses as being saved. Even though they were not showing as saved, I did try to connect those devices with no success. 

I do not want to run with MAC filtering set to "ALLOW ALL".  If anyone knows of a workaround, please let me know. Otherwise, I may need to return this XB8 and go with another ARRIS unit.