Overall good, but one major issue
I'm sure by now you're tired of hearing this, unfortunately though, this is an issue that needs to be addressed.
Overall the game was very good, well put together, with effective graphics and gameplay...
The wall jumping was, and many before have pointed this out already, unreliable at best. I enjoyed the game and the challenge of both the puzzle aspect and manipulation of the character immensely up to level 16, where wall-jumping became crucial. At this point it seemed like it didn't matter if I held down UP while alternating LEFT and RIGHT, or if I tried to time it, the character would always miss by just a little bit, and end up sliding back down. Half the time I can't even make it up the first corridor.
This single level became singularly aggravating, frustrating me to the point where I had to take several cool-down periods before I could resort to breaking stuff to vent my frustration.
If you're stuck on a level for half an hour, it's a tough level.
If you're stuck on a level for 2 hours, it's probably user incompetence.
If you're stuck on a level for a day...Well, there's probably something inherently wrong with the level.
I know people have beat the game with no problem, but I also know I've read more than a few comments bringing up the wall-jumping difficulty, and so far this issue hasn't been addressed.