How to setup properly?

[igisav]

Hi,

I was trying to install Menu just like in README, by dragging ./Pause Menu Assets/Prefab/Pause Menu.prefab into my Project View.

But got following error:

Assertion failed: Assertion failed on expression: 'modifications.empty()'
UnityEditorInternal.InternalEditorUtility:HierarchyWindowDrag(HierarchyProperty, Boolean, HierarchyDropMode)
UnityEngine.GUIUtility:ProcessEvent(Int32, IntPtr)

Also, if I check this project and run in Unity, there are a lot of errors...

Is this due the version of Unity I'm using (2017.2.0) or have I missed something by installation?