Problem: We are trying to import and transform a SID file into Civil 3D 2007 using Raster Design 2007. However, Raster design throws the following error, "The Coordinate System Chosen for this Image is Invalid." We get this error when going to Image > Insert and attempting to choose a coordinate system for the transformation.
Answer: Very simple - make sure Raster Design 2007 is the only version of Raster Design on your computer. Uninstall Raster Design 2006 and the error should be fixed!