[Spaceships] Homebrew - Alternate Contragrav

[Flyndaran]

I would think simple contact of anything capable of scuffing paint would count. It wouldn't have to be vehicle damage by any Gurps or even common language definition.
But defining what percentage is lost over time scuffed, as that would likely matter greatly for anti-gravity purposes, I have no clue.

On a more serious note, I'd imagine anyone above TL 5 or so would try to laminate or cover up the active paint with some kind of ablative material even if it acts as dead weight.