Strange rendering Bugs with the new UI System

As you can see in Picture 1, i have a complex UI with an Scrollable List which contains 6 Elements at the moment. (This UI is partially exported from my real game project, because i couldn't reproduce my issue with an smaller example)

But unfortunately i have a very strange bahaviour if you look at the next picture.

The 6 Elements are not rendered properly. If i remove or deactivates a random element from the canvas, the 6 elements are fine, but an arbitrary other element is starting to behave abnormal.

I included the test Project, so you can check it out.
Is this a bug, or am i using the new UI System in a totally wrong manner?

 

I accidentally found out that i was on an old Unity version (5.1.0f3). I didn't know that the "Check for Update" mechanism in Unity is bugged and is always saying that i'm already up to date. So i couldn't know that there were released 3 newer versions in the meanwhile -.-

But im happy that my problem is gone with the newest version