From your description, it sounds like you are on track, but you can check by going to the move tab, then under “feature” in the upper right-hand corner, choose the feature you want in the drop-down menu. Just below that, it shows the x,y,z and Rx, Ry, Rz of your tool center point. The x and y values displayed there should match the x and y value of your current_to_feature (make sure the tool center point shown is the one you are using).
Are the axes of your feature pointing the same direction as the axes of the base feature? If not, you will also have to perform a coordinate rotation to get the correct values, since get_actual_tcp_pose() returns only base coordinates. We worked out coordinate rotation here:
http://forum.universal-robots.com/t/ur5-vision-coordinate-system-difficulties/499
Good luck!