Again, I have not played for a while, and both Moposite and Elma Online sites seem to lack internal-maps feature, so I am at a blank.Haruhi wrote:15 has two hard parts - the drop after the last apple and the drop at the end. Should be possible with xiit though.
However, it seems to me, from memory, at least in level 15, that one can just continue forward after the bottom-right apple and wall-hate it a little bit through braking (wall-hating refers to using it for anti-speed purposes, and, conversely, following its curves and being sensual with it means wall-loving).
The third type of wall interaction one can have is wall-bouncing. This one seems quite neutral, which is the reason it is in a separated category.