It looks like that piece of software hasn't been updated in a while... the author lists only Jaguar and Panther as compatible operating systems, showing how dated it is. While most people have had good luck running it on Tiger, most likely it's a PowerPC-only application and won't run on an Intel-based machine.
I thought that maybe Rosetta would be able to help, but that would likely mean you'd have to run the Finder in Rosetta, which may not even be possible, and would decrease the speed of the Finder a tad.