This is a known issue with our latest official version of the controls which is caused by a problem with the Schedule View localization interfering with the Chart labels localization in some integration scenarios.
This problem is already fixed and you can download the latest weekly internal build from your Client account.
Alternatively, as a workaround we can suggest you to add the following line in the MainPage constructor (just after the InitializeComponent(); call) and this should resolve the problem as well:
Hope this helps.
the Telerik team
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