Thank you for contacting us!
Field labels are related to the backend language of the Sitefinity site. You might be in a mono-lingual mode but what is the default backend language of your site?
Do you use it with a dutch translation pack, which allows translation?
As far as the hard-coded labels are concerned, this is a missing functionality indeed.
We are having in mind this and localization support is part of our future releases planning.
I'll be glad to assist you further with any questions arisen.
the Telerik team
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