It seems that in the latest RC versions there are problems with IKEv2. I have these problems too and with previous versions I had worked with Azure and in a test environment.
I am in contact with support to solve the problem.
http://forum.mikrotik.com/viewtopic.php?f=1&t=90266&start=50#p569710
http://forum.mikrotik.com/t/v6-38rc-release-candidate-is-released/102037/220