Coc form and registering for Continental Europe?

[Trash_panda]

Has anyone used the icoc(?) Form for registering their cars in continental Europe so they can drive into city centres and not have issues with the local constabulary?

This is for imports that do not have emissions on the v5 and so can't register for ulez exemption. The coc form used to give us the ability to register for ulez exemption but they've apparently, stopped accepting it. Thanks