Wow, thanks for the feedback! I'm glad you liked it! Sorry it took so long to get back to you!
Looking back the tutorial text was a bit confusing. You only ever get to rotate once. If you rotate, you can't rotate again before touching the ground. You can rotate in mid-air if you walk off of a ledge. You can't rotate in mid-air if you have already rotated. Does that make more sense? I'll have to figure out how to explain it better
There is however a "power-up" that I have added to the game that will allow you to rotate twice when you pick it up as well as another power up that allows you to rotate 180 degrees instead of 90. This will be included in the next update with some new levels.
The mouse wheel was a bug with the input manager. It will be fixed when I upload a new version later today. In the later levels it will be helpful to "zoom out" and see the entire level. In that build of the game either pressing the middle mouse button or the space bar would zoom you out and then pressing it again would zoom back in.
I really like the idea of using the arrow keys for the rotation instead of/in addition to the mouse! Thanks!