As of R2014b, Handle Graphics 2 (HG2) started being used. One aspect of HG2 is that uicontrols no longer automatically render on top: now if there is an object that is drawn "after" a uicontrol at the same Z depth (typically 0), then the second object will block the uicontrol.
If it is a GUIDE GUI and you go through it carefully, you will probably find that the "Import SWC" section is parented to the figure rather than being parent to a uipanel that is on top of the figure, and you probably need to change the Parent property to the uipanel.
