About Using ECAD Assemblies
When you are working in an ECAD assembly, you can perform any of the following operations:
• Enter ECAD-MCAD collaboration
• Save the assembly as an EDA file
• Save the assembly as an IDX file
• Use the assembly to compare against during ECAD-MCAD collaboration
To perform the previous operations, remember these criteria about the ECAD assembly:
• Cannot be in an exploded state—Restore the assembly to the unexploded state.
• Must be in the Master representation—To change the representation of the ECAD assembly, right-click the top-level assembly or subassembly and choose > .
• Can be fully flattened—To preview the flat state of the board in the ECAD assembly, click 
in the Graphics toolbar. The flattened board opens in the Flat Pattern Preview window. If the board cannot be flattened, you can edit it to resolve the problem.
in the Graphics toolbar. The flattened board opens in the Flat Pattern Preview window. If the board cannot be flattened, you can edit it to resolve the problem.