Edit: IMPORTANT! The following review covers an incredibly outdated version of the game and does not reflect the current state of the game.
The gameplay is alright, but the lack of checkpoints just ruins the main game for me, screwing up ONE puzzle will put me back to the beginning of Feedwater, and I don't like that at all. As for graphics, they are pretty meh and don't fit together well, perhaps hire a pixel artist to work on making visual assets? (For example, the balls could take advantage of a scrolling texture to properly imitate rolling in a 2D environment)
Edit: Okay, so I am going to be documenting some puzzles in Feedwater that are too difficult to clear:
Bottom left: Arrows are clumped together far too closely to be capable of dodging them, I also cannot document the path I should take to complete this puzzle.
Left: Requires an absurd level of timing to fire 2 groups of arrows at once JUST to clear BOTH walls
Top left: Is actually the only puzzle I can beat here, however boulder recovery is impossible so if I slip up, I have to deal with it. Also failing to time this puzzle adequately is far too punishing for the player, perhaps switch this to a mounted crossbow section?
For all puzzles, PLEASE add checkpoints when I successfully open a door on the right. I could screw up ONE section and have to redo SEVERAL puzzles just to regain progress. Other puzzle games don't punish players for screw-ups by throwing them back to the beginning, this WILL harm the popularity of your game, even in this demo.