I upgraded from 4.3.1 to 4.6.1 and im missing UMG unreal motion graphics . theres no option in “editor preferences” for Experimental tools. for UMG … Not sure what to do.
Because it’s not experimental anymore 
Have a read: https://docs.unrealengine/latest/INT/Engine/UMG/
What i mean is, I dont even have user interface options in my creaste button list
Are you really sure that you use the 4.6 version? -> create a new project - choose 4.6 - check if you can see it now 