The open source Zircon engine ("DarkPlaces Mark V Project") is a modification DarkPlaces engine with a mouse driven menu everywhere, ALT-ENTER fullscreen/windowed switching and 88 other enhancements to support user/mapper/mod coder ease-of-use and optional conveniences for those interested in a "1996 Quake" experience. "csqc_full_width_height 1" in console when running Arcane Dimensions at this time It is hoped that some/many/all of these enhancements will eventually make it into official DarkPlaces. The Zircon engine seeks to keep full compatibility with DarkPlaces so either engine can be used interchangeably.
This is the Mountain Terrain Test compiled and modified to work with Quake 3 Arena, particularly Quake Sandbox (Quake 3 Arena and Open Arena can't load this map due to the size -- at least not with default memory settings, Quake Sandbox -- a derivative of Open Arena supports higher capacity maps and can load this map). This is a largely finished port of the Mountain Terrain Test 1 for Zircon/DarkPlaces to a Pure Quake 3 map format. Can load this map: Quake Sandbox, Zircon Engine and DarkPlaces. Probably FTEQW. To run map, place pk3 in game folder --> "map mountainbaker1_q3" (If you want to try this in Quake 1 using Zircon or DarkPlaces, don't use this one -- use the one made for DarkPlaces compatibility -- it's in the files section).