Fred,
No, I haven't emailed him. I tried a few different browsers to see if it was anything in my settings (or not liking my not 'modern' browsers as google keeps reminding me).
In the end I decided it wasn't worth the effort. I've enough scraps of material lying around to knock the bits together in an hour or two, which would leave me with a kit of bits, which is exactly where I'd be if I had managed to order the kit in the first place, and I've already expended that much time staring at the website.
Besides, I've forgotten almost all of my "Deutsch als Fremdesprache" (German as a foreign language), well, apart from the essential, 'Ein bier bitte'.
Chris