Marco,
Thanks for the feedback, & don't worry , I think that people who ask for feedback and want to shoot the messenger are pretty ridiculous.
It is interesting that the <pre> code was the one that you had trouble with. I used the "bluefish" editor (open source) to format the HTML. I noticed that their tag for preformatted text was simpler than that used on previously published tutorials. I tried editing those tags to make them like the published tutorials, apparently I missed the quotes. It would be interesting to see if the code right out of an editor like bluefish would work, it would be nice to be able to use an editor that would produce code that is essentially correct by construction.
About the scheme code & style, I guess I would say that I am not a programmer, so the criticism does not hurt my feelings. My goal was to write code that is clear and avoid writing bad code (to have it called kind of 'C' like actually seems like kind of a compliment). I think it is better to avoid opening up a debate on coding style, I have seen them consume a lot of energy and often fail to resolve much. If I do write another tutorial, the one that I am thinking about be just gimp-python anyway (it would be harder to write in scheme).
