OpenWRT on PC as gateway time restrictions

Hello everybody. Started this thread for help about configuring a home network as the attached drawing. Need to make a PC as "Time restrictions gateway" using openWRT, because of easy use, access and rules configuration for times depending on MAC addresses. I used pfSENSE before, but I need something more simple, as I do not need all those extra and complicated rules. So as looks in diagram, the openWRT PC will act for managing user access filtering by MAC address, in periodically days and times. Please, how should I setup the openWRT for doing this? Any help and suggestion is welcome. Thank you all, and thank everybody working on this helpful site.