Hello, we notice that when the valueAxis is disabled while some of the series are choose to plot onto it, then the position for another UI will be misplaced.
Example: http://jsfiddle.net/YeongCY/k0znm673/
I normally do not use smileys here but this is something... At this point I don't have any idea why it behaves like this but it will be addressed early next week.
Thanks Karlis.
This has now been fixed. It will be released within this week as a hotfix for 1.15.