Duplicated blueprint components do not update when altered until compile is pressed. They don't accept new parameter values nor do they respond to any transforms.
1. Open Editor (any project)
2. Create new blueprint
3. Create Box component
4. Rotate box on an axis (z axis 45 was used for this test)
5. RMB box in components tab>Duplicate
6. Attempt to rotate new box component.
New box does not rotate and will not appear to move if moved until compile is pressed, at which point it will update to the new position/rotation.
New box component updates as the widget or details pane is altered.
There's no existing public thread on this issue, so head over to Questions & Answers just mention UE-18371 in the post.