Same problem here. i've got 3 of them (via pixel-precise selection of the click zones), but the bottom/left one will not unscrew. i had this same problem on the first door: had to click at least 25 times to just the perfect 1-pixel-wide click zone on each of the boards which were blocking the door.

Now i'm stuck because this one screw won't trigger, leaving me screwed 93 minutes into the game. >:(

i was all ready to give this game a positive review, but getting stuck this way is exceedingly disappointing >:(.

GOT IT: that last screw came loose when i clicked about 50-60 pixels below, and 20-30 pixels off-center, to the right, of the screw. i swear, i had to spend more than 5 minutes on that one single screw, though.

Thank you, sgbeal!

The game need be optimized, i had some problems with the accurate with things on many puzzles.

The First Gate
The Saw
The Potion
The Dungeon
The Screwdriver with R.I.P ( I here right now , and try to use on any zone, and still not working yet)

Oh man, this was seriously frustrating.

Thanks sgbeal! The fix was just how you described. Except for me (btw - Linux Mint 18), the sweet spot for all but the top right screw was below and to the left (vs. the right). But for the top right screw, it was right where you said it would be.

Thanks again. I was about to give up on this game.

Thanks for help!

Thank you. Once I knew the hotspot was below and left, I got three of them off quickly, but the upper right one took 6-8 tries. The hotspot was all the way on the grass.

Same problem. I hate pixelhunting.