It might be useful to others if you post your code someplace -- the HTML /JavaScript, and whatever webview handler code -- a few folks have asked about xslt over the years, and it sounds like you got it working.
Welcome!
This is the community forum for my apps Pythonista and Editorial.
For individual support questions, you can also send an email. If you have a very short question or just want to say hello — I'm @olemoritz on Twitter.