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I'll start somewhere between "What's a Creator?" and "Squarewave transparency" (lol). If I say something you already know just ignore... I dont know what your graphics tool is (I use PhotoShop) so I'll just describe in concept. Hands for the most part rotate from the center like a propeller blade. If you're making your own hands, you have to account for this equal dead space at the heel-end of the pointer. Let's look at your minute hand. My pixel dimensions are probably not the same as yours, but my numbers are just to describe the scenario. Here is your hand now. I'll cut off the unneeded air at the top.
OK Let's look at the width first:
As I said hands rotate from the center so you hand MUST BE DEAD CENTER form left to right. Seriously, the centerlines on hands are probably the most important attribute. You can crop the image however you like, but the space to the left and right of the vertical centerline must be exact in pixels.
Next is the height and for that you need to know exactly where you want the hand to pivot from. This will mark the dead-center of the hand graphic. You need to measure in pixels the exact height from the center point up to the tip of the hand.
Lastly, remove the background and save as a transparent PNG file. Then the hand will rotate correctly in the Creator.