Some of those maps are playable while other are only artistic maps. This page is to list all maps I found while browsing various forums which I found simply awesome 😀

Arbor Vitae by Philip Klevestav and Helder Pinto

Aqueduct by Mozi

DM-Primal by Ben Burkart

Dungeon Escape (UDK adventure level) by Chris Holden

Reclamation by Mozi

Solitude by Mozi

Zest Foundation by Thiago Klafke