I love your tool, it has a lot of potential! Unfortunately, I'm getting the 0-size-file bug for pdf and pdftex output (which I see you're working on). Also, when I output pstex, the output is missing the closing '$' characters at the end of special strings.
Thanks again for your hard work!
Edit - This is not actually a bug, but an anomaly of the special text previewer - I accidentally left off the closing '$', but the text previewer displayed the math text correctly, so I did not realize I had left off the '$'!