Oops!
If you've tried to use the modified version of Scintilla that I described in my MSDN article, you will find that the zipped sources don't actually have the changes that I made. That was my fault; when I was packaging the sources, I had two versions of ScintillaWin.cxx around, and I picked the newer one, which (sigh) was the wrong one. Anyway, here's a link to the correct version of ScintillaWin.cxx with TSF support.