I've never had a LPGUK approved installation in my life, nor had any certification to the effect that the installation has been inspected.
Most insurance companies won't accept a LPGUK issued certificate, only an engineers report, or an MOT.
In fact if the current MOT postdates the LPG installation, this is all that is required by the majority of insurers.
The original LPGA COPII were a nonsense, and unlike things like GasSafe in the case of household gas installations, not mandatory in any way shape or form.
Brian