As to the quest about display routing, the answer is yes, I want to display my GNU/Linux window on Tiger.
Hello Axeman15 I use ssh x11 forwarding between Tiger, Panther and linux machines without any problems. I have not manually set any display variables I just leave them as they are out of the box. I know this does not help you much however you may want to try resetting all your display variables to default.
I also upgraded to the most current stable release of openssh on my Tiger system.
Until you work this out have you considered using VNC?
But you should know that on day 1 of using Tiger none of my x11 forwarding would work using ssh -X, only ssh -Y would work sporadically.
I had a font issue with X11 and this caused a lot of forwarded X11 apps to crash.
To fix this font issue you can run this command in the terminal
b sudo fc-cache -f -v
Now that I have SSH X11 forwarding working correctly in Tiger you still have to use ssh -Y