Thanks et merci guys! Your suggestions really help cut down the trial-and-error solo approach! Hope this helps others and is not too off-topic
Erik--I read somewhere about setting the MTU for Macs, so I'll hunt that up again and post back. Worth a try. My cable connection is capped at 1 Mbit/sec up and down.
ą et voilą--yes, except I use
http://192.168.59.1/Forward.htm. Since I set for Static IP WAN, I also set each internal IP in the Advanced->Static Routing pane (this was recommended by tech support for my previous software). I wonder about setting the hop count. As much as possible, I tend to leave everything at default. I've tried the firewall on (open to 6346) and off without noticing much difference, so I tend to leave it on (laptop goes to work every day).
Current hosts still show high 30's this AM with cpu% usually in the 20's. With IP's unforced, the iMac G4 is connected to me as a leaf, so that works (but really messes up the stats if files are transferred!). Hiding Connections does seem to help too, but curiously, LW will sometimes disappear in Process Viewer's list when I view connections.
In the Forwarding pane I didn't touch the UPnP or Port Triggering , but here's how it looks for the record