I just started working with Stylus...
Discovered the following problem. When i set custom XSLT processor for a scenario, the system says it cannot find the file specified. The system variable Path is set properly, i can call my processor from command prompt without specifying full path.
When i set the path in global application Options, it seems scenarios do not see it so i have to set full path in EVERY scenario. This can be painful if need to have a lot of scenarios, as well as it makes the project usage impossible at other machine.
Stylus 2010 demo
Couple of other suggestions:
1) Nice to be able to add many files to project from Project menu, not only from File Explorer.
2) Nice to be able to sort files in project folders.
I like your xsd-to-xsd visual mapper idea, it can save lot of time for me.