I came over this extension called 's4u Import DXF (for Sketchup Pro)' [Link: http://extensions.sketchup.com/en/content/s4u-import-dxf ] which pretty much solves the issue of importing the smoother curves. The only limitations are, the extension is [highlight=#ffffbf:dwz315js]not free[/highlight:dwz315js] (Use 10 day trial to test) and works only on [highlight=#ffffbf:dwz315js]Pro versions[/highlight:dwz315js] of Sketchup. Goodluck!