Chief Architect is architectural and interior design CAD software.
- Open a 3D model in Chief Architect
- Select File → Export → Export 3D Model (3DS)
- Uncheck Truncate Texture Names and select Export
- Create a new folder with the name of your project.
- Open the folder, name the project and save the model. (You're also saving the materials)
- Navigate to the new folder and compress it into a .zip file. (This is important if you want the materials to show in your online models) See video around 4 minutes.