Yeah, Warp is right. The touch screen controls kill it. That and the physics engine. See, my biggest qualm with the game is that the entire game's concept is for you to be creative. But the controls absolutely prevent any creativity from taking place in the actual puzzles. A good example would be this:
There's one stage where you essentially just have to run down a big hill and get to the end of the stage, so in other words the average person is gonna go "Okay! Time to make a vehicle!" Well, me being creative, I spawned a sled, used some ropes to attach it to a dinosaur, then attached a piece of meat to a fishing pole and made it so the dinosaur would pull me. Well after a few seconds my plow started sinking into the ground, until finally it went all the way through and killed me. I was annoyed but figured it was a fluke. I tried it again but with a triceratops since I thought i might've been going too fast. It happened again. So the third time I was tired of wasting time by spawning things and, you know, trying to have fun, and instead I just spawned a motorcycle and beat the level with that.
Also going back to the physics problem I mentioned. There's a level where you have the star frozen in some ice above lava, and a tripwire in front of it. So I attached the ice block to an ankylosaur. I tripped the tripwire, the ice block pulled the ankylosaur back and everything fell in the lava, game over. Repeat with an elephant. Same result. Repeat with a bus/ Same result. So I go onto Gamefaqs to see how to do it, what was the solution? Attach the rope to an eagle and have it fly towards some food, and that worked. Okay, so an eagle flying is more powerful than a dinosaur/bus? I don't know, it's just insanely frustrating...