@Electroplated, right I see what's happening.
The RoninGUI will run on Tiger and Leopard on an Intel Mac only, it is not compiled to support the older PPC architecture Macs. I will not be able to provide a release for these systems as I do not own them and I have no way of compiling or testing the GUI with them.
It would be possible to try and compile the RoninGUI from it's source files, to make an executable for Tiger or Leopard on a PPC mac. All of the RoninGUI source files are available from http://sourceforge.net/p/ronin802
Another option would be to use the Linux version, you can install GNU Linux to your Mac alongside the existing operating system. Certain distributions of GNU Linux, such as Ubuntu and Mint, are really easy to install and set up.
I had a hunch that the GUI wouldn't work with OS X Lion, I don't have a copy of this operating system, so it has not been compiled or tested on it.
I'm going to the Apple store this weekend to see about purchasing OS X Lion so I can compile and test the GUI on it. I'll keep you posted on this, will let you know as soon as I have it running.