I would not recommend to try to align objects using rotation around specified point, since landmark registration is much more reliable, faster, and accurate: you just specify a few corresponding points on the objects you want to align and you are done - no manual tuning of several sliders are necessary and result is guaranteed to be optimal. There are several landmark registration modules available in Slicer, but probably the most convenient and powerful is Fiducial registration wizard module in SlicerIGT extension.
Anyway, if you still want to do rotation around centerpoint (there are valid uses cases, they are just rare) then you can use this example in the script repository: https://www.slicer.org/wiki/Documentation/Nightly/ScriptRepository#Rotate_a_node_around_a_specified_point