I built a simple barrel vault and then copied and rotated it to make both vaults intersect.
I then selected the entire object, made a Tag (Double Vault), and assigned to that name using the Entity panel.
When I turn off the Tag Double Vault in the Tag panel, some of the geometery is left behind… six lines and some surfaces ie. a dotted curved plane. They obviously did not get included in the Double Vault tag…
Any ideas how to prevent this from happening again and/or how to fix it?