I want a custom SketchUp extension that streamlines DWG/DXF exchange. The core focus is reliable file-import and file-export routines that keep model information intact. Key capabilities • DWG/DXF import must preserve every original layer so I can toggle visibility and organise geometry exactly as it was authored. • DWG/DXF export must write out attributes from my SketchUp components, groups and entities, allowing that data to travel back to AutoCAD without manual re-tagging. The add-on should install in the usual .rbz format, appear in the Extensions menu, and run smoothly on current public releases of SketchUp Pro. Written in Ruby with the native SketchUp API is preferred, but I’m open to an alternative language route if it delivers the same seamless user experience. Deliverables 1. Signed .rbz package with the functionality above. 2. Brief setup and usage guide (PDF or markdown). 3. Source code with clear comments for future maintenance. I may later expand support to other formats such as OBJ or FBX, so structuring the code for future extensibility would be appreciated.