Amazing entry!!
I'm nearly finished I think (into the font files now), but I've gotta run now... will come back a bit later and finish it.
Scrolling windows as a mechanic was very interesting and often adds greatly to the challenge of a level.
Edit: Finished it this morning - very well done and an amazing number of levels!
Edit 2: I forgot to mention - I started playing the web version and ran into performance issues once I hit the first of the larger levels (so slow that it was unplayable). I then downloaded the desktop version and restarted with that and it was fine... so the performance issue is probably just on the web version.