The comments about the earlier levels being strange and/or too easy is cos I didn't get time to finish the game
I wanted to have those as "tutorial" levels, each with its own little explanation at the start before you play, explaining what certain things do, and show you how to play the game.
Level 5 is the first hard one, and then 7 and 8 are the hardest
If anyone wants the codes to skip the levels, open up the source, and scroll right to the very bottom, and they're all there.
The first code is for getting into level 2, the second for level 3, etc, etc
I hope that those who didn't like the earlier levels will try skipping to the harder later ones ( 7 and 8 are tricky

).
Thanks for the comments, though, they're invaluable
Jess.