If you do not have a current copy of the Design User Manual you can download it in PDF format by opening DS|Design, going to the ‘pull-down’ menus Help > Online User Manual, for reference the DynaSCAPE product manual URL is: https://www.dynascape.com/downloads/
How do I import an AutoCAD file?
You can import files up to 2016 in DS|Design by going to File>Import> AutoCAD® DWG/DXF as a new drawing or AutoCAD® DWG/DXF into the current drawing. After importing a DWG you will have to verify that it is to scale and if it is not, then you will have to rescale it, remove any unnecessary geometry and revise any geometry to DS|Design Layers. You can find detailed instructions with screen captures in the Design User Manual, section entitled Importing an AutoCAD® Drawing into DynaSCAPE on page 17.2 to 17.8