Yes, the Roto cups are supposed to rotate with the limb as they limb changes angle on the riser. That's where they get their name; ROTO (meaning rotate). You should probably take this back to your dealer and see if the two of you can figure out just what's making it hang up. Probably a complete disassembly and try to rotate the cup by hand. Maybe use some machine bluing on the rocker portion to see if there is a high spot in the riser finish making it stick.
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