It's happened on normal mode for me, that's the only one I've been really playing so far. It SEEMS to be happening when using the shovel immediately again after/during a clear (spamming it; I do this to dig from underneath while counting to get quick horizontal lines). Maybe you can try and see yourself? When the screen is close to full/speed is fast I've had it also cause game overs (when the block hangs it seems the game has registered it as a such). It seems to happen regardless of how full the screen is.
Also found the bug on my own, already mentioned below, where the hose can press a block down to the bottom to get rid of it (I actually like this bug though as it can help me to set up tactically and avoid the crane + the screen moves anyway so it's not a BIG exploit. Will echo another user that the crane item slows the entire game down compared to the others; maybe a good thing maybe bad (getting the crane with an almost full screen is frustrating) can't decide.
Also dk how to feel about the random nature of the shovel. It removes a certain amount of skill from the game to have it do random things (to not be able to control which pile to fill up; to a certain extent at least)?
Will also agree with the user below who wanted to see separate game modes for the different objects (even though them switching is the entire gimmick of the game). Dk if that would fit into P8 but hey... Would be a nice optional for some other version if not.
With bugs or not (well... Ironically at least one bug in the game controlling the blocks as others have also pointed out:P) idc as I will purchase to put on a handheld in its current form anyway once I've got some spare cash:)
Edit: Just to copy from below 25840 is my max score (it would seem the score stops here? Because I had over 30k this game)
Edit: no the score works fine; I have a saved one of over 30k now. However sometimes I get a minus score for some reason. It's weird. What's the reason for this?