Ok, the R2 is almost ready to replace the R1. Did a first test today and almost everything works, except my TV receiver for streaming TV service of my provider. In the old R1 there was a switch module which was nice enough to forward all trafic on 1 incoming port to a tagged vlan on the wan port, including DHCP request.
In the R2 I seem to have a config issue. The iptables logging shows all DHCP requests as incoming data on the bridged port, instead of it being bridged. (forwarded to the other port) In the R2 I need to somehow get traffic from lan0 to wan.4 and back without the kernel interfering, including DHCP requests and the returning answers.