Thanks to Marc and others who offered advice, I completed my little project to make an iTunes visualizer plugin with a Scheme REPL. I had previously got it working with Tiny Scheme, but wanted a more robust Scheme implementation, with a compiler.

For anyone interested, you can download scmviz.tar.gz 

If you download it and unpack the archive, you'll find a README file with instructions.

>>> Note this currently only supports intel Macs running OSX 10.5 or later. <<<

You can play music and watch the pretty pictures, or add your own code in scheme to make it work differently. There's a programming guide along with some sample code to get you started. All you need is a text editor.

This is my first project embedding Gambit as a library, and I'm very impressed. It went together with no problems at all. I made a few hooks into the Quartz 2D framework for generating the graphics, but it's not by any means a complete interface. 



Neil Baylis