Rotations and registration points

I know there have been a million questions about registration point adjustment, but I can’t seem to find the answer to my problem. I’m trying to make a propeller clip, but the center of the image is not exactly the center of the mc. I am trying to adjust the mc contents to line up with the main timeline mc’s registration point and then add a timeline effects–>transform/transition–>transform to give it a looping rotation. When I do this, the rotation seems to use the parent mc’s registration point and the rotation animates slightly off.

I hope I am making sense. I am pretty new to Flash in general and I might just not be aware of a better way to animate this rotation. Anyone have any suggestions?