Re: "While you're here, could you just..."
"ND accompanied by a signed waiver of their 14 day cooling off rights."
I doubt that would have any standing (I'm assuming this is for UK consumer rather then B2B or anything in that lawless place over there) other than to make them thing again before you go ahead. As has been said here when discussion EULAs, statutory legislation overrules contract law and consumer rights are statutory.