Moving segments
Make sure no tools are highlighted.
Double-click the prosthesis in the visibility tool to make it transparent.
Click Unlock 
on Top.
Click the bar in the 3D view to display the handles. Use the white segment handles to move the segments or extensions into the proper buccolingual position.
Tip
From the top view, the higher top handles may hide the segment handles. Slightly tilt the model to view the segment handles.