I download the package “Unity Samples: UI” from unity assetstore, and import to my unity5.2 project , the scene “Menu 3D” displays correctly , everything goes well. but when i import this package to my unity5.3.1f project,the scene “Menu 3D” displays incorrectly, each UI object is invisible in view, though they can be found in Hierarchy, when i create a new UI object in this scene, strange things happend, all UI objects can be seen now,but when i delete the UI object i created , all UI objects are invisible again,i don’t know why this happens, who knows how to solve it?
URL of the unitypackage"Unity Samples: UI" is :Unity Asset Store - The Best Assets for Game Making