Hello Adrian,
Thank you for the bug report. I looked into it and there was a small problem which will be fixed in our next internal build. For now if you are going to use only one item you could change the MinimizedItemsPosition to Right and I couldn't find a problem when there are more than one items:
With this code everything was working fine.
I've updated your telerik account and if you have further questions feel free to ask.
Regards,
Zarko
the Telerik team
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