Yeah that last part of what you said was really the feel and idea I was going for so I am glad that people could understand the idea even though it may not have had a perfect level design for it. Design the levels was already a huge headache even with how few abilities there are and how short it is.
As for the wall jumping it was originally a bug but seeing that I kind of liked the idea of allowing wall jumping I built the levels with it in mind. That is why you have to go through a very curvy maze like part right before you have to actually use it. The intent was to make the player hit a wall so they would see it's kind of sticky and then when they see the next obstacle they would hopefully have figured it out from that that they could wall jump.
As for the Java thing I normally make software and am very used to JavaFX and have made very few things in game engines so I felt more comfortable in it. I likely will not be doing it that way again in the future though. I spent too much time just getting the normal basics of a game working that in a game engine would be working from the start. This was my first game jam and my first "real" solo game. I have made games before but nothing like this.