I try for hours to get a connection from local machine (green 192.168.100.2) to a motioneyeos raspberry (orange DMZ) 192.168.200.3 but it just will not work out. I set 192.168.200.1 as DNS.
It works out fine on normal router but on ipfire orange as 192.168.200.3 there is no-go
E.g. why is this INPUT being dropped within DMZ Zone - i have no rule to deny that.
it looks like your GREEN and ORANGE zone share the same subnet (192.168.200.0/x).
Please assign different subnets to each other - does not have to be a full /24, although this is the most common setup -, reboot your firewall machine and try again.