Mucking around in the environment made me feel physically sick, but I did that bit. Unzipping tablet-encode cost me over half an hour as I don't actually have bit-zipper on any of my computers, but I got there in the end. They seem to want your first born in payment for that.
Running the command was complex - took me several shots to actually get it exactly right - but I have run it. It has output a response, the only bit of which I understand is 'be vewwy vewwy quiet'.
tablet-encode -p good D:\Video\SomeFilm.avi F:\.video\