Their API documentation is OK I suppose, although I wish the API was more .NET targeted. Also can’t say I’m impressed by their documentation on how to get started using this stuff.
Either way, here are the steps to do a simple XSLT transformation of an XML document.
var xslt = new FileInfo(@"C:\path\to\stylesheet.xslt");
var input = new FileInfo(@"C:\path\to\data.xml");
var output = new FileInfo(@"C:\path\to\result.xml");
// Compile stylesheet
var processor = new Processor();
var compiler = processor.NewXsltCompiler();
var executable = compiler.Compile(new Uri(xslt.FullName));
// Do transformation to a destination
var destination = new DomDestination();
using(var inputStream = input.OpenRead())
var transformer = executable.Load();
transformer.SetInputStream(input, new Uri(input.DirectoryName));
// Save result to a file (or whatever else you wanna do)
Sure are a lot more steps than I feel necessary here, but oh well… that’s how you do it anyways *shrug*