RB2011UiAS-2HnD-IN can't access internet

Hi guys, I’m reaching out for help after being stuck for a few hours trying to replace my awful netgear router.

I have a rather simple setup, my router is plugged into my cable modem (CM500-100NAS), and all the devices connected directly to the router.

When I try to connect the modem to the RB2011UiAS-2HnD-IN (on port Ether1) and my laptop on port Ether2, I can connect to the router just fine using winbox. I tried to use Quick Set to set it up as a Home AP, with the port set to the default Eth1.
Address acquisition was left on automatic, but the IP netmask and gateway fields remain blank.
I’ve tried to set it to static and using the IP of the router I’m replacing, 255.255.255.0 for the netmask and the IP of the modem as the default gateway, but no luck either.
The local network options are set mostly as default, with DHCP, NAT and UPnP checked.

If I swap my old router back in, it connects just fine.
I’ve also tried to daisy chain the mikrotek behind the old netgear, and in this case automatic address acquisition does work and fill out IP/netmask/gateway.

Please help, I’m very confused at this point.