Does any one have an idea how big the biggest image I can include in a quest game is? The best I could find was the recommended size for the cover art.

I do not think there is a technical image, but it will look rubbish if it does not fit a screen with room for some text too. And that depends on the size of the players screen, or rather the size of the browser screen.

Bear in mind there is a 20 Mb limit on total game size for uploading, and big images wil use that faster.

Thank you, I'll keep that in mind as I progress .