Nice gear mechanism - B dropped the ball that was very hard to see but B can't get back to the center to get to the win. Hint please - assuming the mechanism keeps working. Here's a sample of the mechanism not working - it failed more than once. Spoiler
Cancel hint request - I used MekoStudio as you've hidden things previously and I found a hidden item that didn't fall previously. I dropped a star as I can't encourage hidden. Timing the low ceiling issue for B to get back was starting to become tiring as I needed so many attempts and had to wait for the mechanism to cycle back around. Finally got it.
I really enjoyed playing the level. I'm going for 4 stars as it felt like tricks were used as an alternative to actually exploiting the main mechanism or central building more. Like a @richardfu_ trick invention in the middle of a @Star Penguin pure logic level. The main mechanism is good fun.
@Meko Guy @Block builder Thanks for playing! I began to try to incorporate machinery into my level, and started to change my mind to make some levels that were not too difficult but more interesting. @Meko Guy I marked out the hidden place with red squares to make it easier to find.