First off, great idea to have the game as a demo on the web before you release it. I have just had a play on it and here is my thoughts....
I think that there is probably the framework for a good game in that demo but I think it needs work refining. When I say that I don't mean the movement or the interactions(which seems proficient enough) I mean the gameplay.
To be honest I wasn't sure what type of puzzle game it is supposed to be? If it is a stop and think puzzle, there was hardly any thought needed. If it is supposed to be a speed challange I didn't really get any sense of urgancy either.
I didn't really get any sense that I was actually really doing anything at all other than adding a block to what ever same colour block i saw first. I quickly found that I didn't need to spin the 3D to play the game either (which sorts of negates the 3D aspect).
There didn't seem to be any variation either (or any sign of variation to come). In the end, I did 3-4 levels before I lost interest.. I was really on autopilot the whole time and wasn't really feeling much puzzle or challange comming out.
Two other quick points. I thought that the count of the bonus counting at the end of a level took too long to do. I also noticed that if you paused and go into settings while the bonus is counting is going on, the new level starts on top of the menu.
Over all a puzzle game lives and dies on the actual puzzle. It has to be both challanging and quick to identify the scope of the puzzle iteslf. In its current form, I wasn't getting either.
Thanks for the bug report, I'm gonna fix that right away!
As for the challenge tuning though, that unfortunately just sounds like this game isn't meant for you. I mean, you are correct that it's meant to be more of a speed challenge than a stop-and-think puzzle. I do intend to increase the difficulty so the energy drain starts at the level 2 rate, but beyond that change, most of my playtesters find that the pacing gets very frantic after several levels. You aren't the only person who doesn't find much challenge in this game, but again that simply means you're not really the target audience.
I do think you should checkout the game once it's released because of the interesting camera control I have implemented (the camera control is fairly unique), but it sounds like the game itself is of limited appeal to you specifically. oh well