Very awesome mod.

Nominated!
One question that is probably very easy. I skimmed the thread but didn't see an answer.
In the custom output, what would I need to write to have certain content only appear if an optional field is completed?
i.e. User ticks boxes indicating damages on item. I want it to display: "Seller reports the following damages: (answer output)." If they don't tick any boxes, I don't want any part of the sentence. (I'm also using it for linked images, so I don't want the IMG tags to appear if they haven't pasted a URL in one of the optional fields).
Thank you again for the mod.