(The more I think about it, the more I think you need that route on your router I mentioned below)
Yes I did, had to do it differently but when I run
Wonder if it needed a sudo, or something else..
Anyway, try a
pi@raspberrypi ~ $ cat /proc/sys/net/ipv4/ip_forward
0
(Mine says 0, as I haven't enabled routing, yours should say 1, as the output from the sysctl shows..)
If that's fine (as it probably is based on the sysctl), then it's probably down to the routing tables..
Possibly the default route on the Amiga not getting set...
If you can manually set the IP on the Amiga, try setting the IP (192.168.1.131), subnet mask (255.255.255.0), DNS server (whatever your router is) AND default route (192.168.1.130) that way.
Also, if we can see your Pi's routing table if it doesn't work..
I suppose it's possible your router doesn't like the new subnet. If your router doesn't know about it, he might not pick it up.
If you can add a route to the routing table of your router manually, try that.
So, in the router, it would be a route to 192.168.1.0 255.255.255.0 (/24) and the gateway to that route would be your Pi's IP address on the router subnet (wasn't that something like 192.168.0.x?).
Or, you can use IP masq on the Pi instead of routing, but that is trickier..
desiv