Troubleshooting
Can't Select a Part
Condition
I can't select a part. It's displaying in red.
Cause
You've selected a solid. You can assign only a surface as part.
Remedy
Can't Select More Than One Part
Condition
I can't select more than one part. When I try selecting more parts, only the last selection is used.
Cause
You cannot select multiple disconnected parts. You need to combine them.