Generally, there should be no problems to localize your control. However, based on your request, I have found that the corresponding string resources for the RadDataPager are not translated. I will take care this to be resolved immediately. Thank you for reporting this. I have updated your Telerik points.
On the other hand, I may suggest you take a look at this article for the required resources and follow the approach illustrated in this forum thread. I will let you know as soon as the translated resources have been added.
Please excuse us for any inconvenience caused.
the Telerik team
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