About the black-screen issue; I think this is to do with the specific implementation. In Chrome, I get the black screen; but when I tried it in IE as an alternative, that didn't happen. So if you can stomach it, and you're starting a new game (like me), then you can always try that...
Baffo -- the circle must only contain the Hematite molecule when you release it. Because there's another element present, the circle isn't correct. Your solution works with one small amend -- if you change the final arm to be quicker. Instead of grab, two extends, release and two retracts, replace it with two pauses, a restart symbol, then a four-step cycle of grab, extend, release and retract. You only need to extend it one space to be within the circle, and the changed rhythm releases the molecule earlier, which is enough to avoid this problem and let the solution work.
This is an extraordinary game; my brother showed it to me, and we've been sharing solutions since. It's fascinating trying to find your way to the answer, and even when you don't have the best answer - which I never do - it's incredibly satisfying to see your mechanism working. Excellent!
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