The 47 Mb shape file really looks too big to be processed with RadMap. It will take a significant time to load, and most probably will have very slow performance on zoom and panning. We've made significant improvements in performance of the RadMap on the complex shapes after 2011.Q1. We've decreased initial load time for complex map shapes and made zooming faster when complex map shapes are in use. These changes are available in the latest internal build, so you can try your shape file with latest build.
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