I was doing the 'push the giant block all the way down the pyramid' puzzle (not long after you get the shovel) when I got stuck because this block just decided that it didn't want to fall down from the ledge I pushed it off of.

Has anyone else seen experienced this? It was pretty discouraging to realize that I had to do the whole puzzle over again. If this is common, I may just give up, because it seems like block-pushing is a significant part of the game.

Same happened to me, but only in that place.
Third time i did it it worked.

Have not had any problems with pushing blocks since, but i have gotten stuck other places (like the bottom of a small lake, and inside the wall).
There is some bugs in the game, but just save each time you pass a save-point and it shouldn't be too much to redo.