Inadvertantly created MarketplaceData for an airport, can no longer Build

Using the SDK I somehow added Marketplace Data and can not delete it. Whenever I try to do a Build, I get the following hard error:
“MarketplaceData | Invalid or empty category/section”
How can I fix this?

Umm, I have no experience of it, but can’t you just add a category / section? Sorry if that’s too obvious lol

You must have marketplace data to build your project. This is a new rule sometime ago. Just use the fake thumbnails etc. and it will work. See the samples, KALO airport