Unfortunately the current version of the RadMap can't process so big shape files (384 MB with a DBF size of 285 MB).
Could you, please, provide us with shape file which you were able to load in the version 2010.3.1314.40 and can't in the 2011.1.411.40? I hope we will be able to provide you with some suggestions on loading these files.
the Telerik team
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