I can introduce custom icons.
<pant> I’d love that
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The trouble would be getting people to use them.
Yeah, I guess so. But nevertheless … I also think people who create custom levels may be a bit, well, more alphabetized
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than the average and also may read a thread like this one … if
some authors use this icon then other authors may take on the good example … wishful thinking for a better world, as usual
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but where does pure wishful thinking stop and positive self-fulfilling prophecy begin?
Realistically I would need to trawl through all the levels and edit them to have the correct icon, which would be messy. 
Uhm, “messy”? I guess not. But a LOT of work for you, which was not my intention. So, don't do this. Except perhaps with your own submissions. Haha, I realize that I assume the new icon already implemented
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I think your sticky thread with links to them all is the best plan, personally.. :>
Thanks for the flowers, Annik. But imagine one day a laser mine visits my asteroid and zaps my flowers (heavens forbid! I've lived all my life as if I were immortal, as if only micro meteorite impact could kill me). Anyway, I think such a new icon and the new guide to user-created maps wouldn’t contradict each other.
But hey, I didn’t want to throw a lot of work unto you, I’d wish for this only if it’s just a few clicks. I could quickly do something in Photoshop (I
dream in Adobe Pshop, InDy and AI) if you’d like, though I’m not especially artistic, more the prepress producing guy, layout, typo, cartography etc.