I have little spare time right now, so I just quickly zoomed through the tutorials. When I get a few spare hours, I want to dig into the Trails code itself.
I like Ruby on Rails because of the ease of customizing the auto-generated scaffold code. I spent a little time looking at the generated Trails configuration files, etc. and I am not sure about customizing as far as changing global appearance, etc. but the second tutorial shows how to use Java 5 annotations to change generated form labels, data formats, etc. The second tutorial does show how to change page templates, which is probably what I want: a functional equivalent to global changes of style sheets.