Yup, I watched the whole thing. I wouldn't have noticed the water thingy in level 1 nor the shortcut in level 2 had my brother not pointed it out. I still have a few days left on my Camtasia trial version so let me try and give demonstrations for all my suggestions (although I think you'll only really need the second example).
The shortcut is in the green room. When you come out of the door that's the path to level 3 and you shoot the blocks, you can go up a "floor" and left. Yarr...my directions suck. Hopefully you'll be able to watch the video... >_<
As for the third thing I suggested...well, again, it'll make it ugly. If you're going to contemplate trying to put that in then it's probably pointless to do the aesthetic stunts. I have no idea whether that would make the video more fun to watch or less fun. :\
Anyways, here's the recorded samples:
Level 1 water demonstration: (about 1.02mb)
http://www.kraftfam.org/~erk/misc/example1.avi
Level 2 shortcut: (about 2.38mb)
http://www.kraftfam.org/~erk/misc/example2.avi
Continue sample: (about 3.12mb)
http://www.kraftfam.org/~erk/misc/example3.avi