How a Silencer map works:



First byte: 0x20

Header: 90 bytes
	byte 0: Header version (150)
	byte 1: Maximum players
	byte 2: Maximum teams
	word 3: level width
	word 5: level height
	byte 7: padding
	byte 8: Map parallax (background)
	byte 9: The ambience level (ranges from -27ish to 0)
	byte A: padding
	byte B: padding
	dwrd C: flags (unused, always 0)
	next 0x80 bytes: null terminated string, map description. Fixed buffer.


Radar:
	dwrd: RadarSize
	next 'RadarSize' bytes: radar.  The radar is compressed with DEFLATE--use zlib to inflate.

	Uncompressed radar:
		172x62 (that's 10664) bytes:  A bitmap.  Each byte is a palette index.  Dimensions: 172x62.

Level:
	dwrd: LevelSize
	Next 'LevelSize' bytes: The level, compressed with DEFLATE.

	Uncompressed level:
		Comprised of three distinct sections--TILES, ACTORS, PLATFORMS. 

		TILES: 
			next 'sizeof(tile) (which is 36 bytes BTW) * width * height': The entire map, in tile form.  Array dimensions depend on X and Y in the header.

			Individual tile:
				Each tile has four background layers, one track layer, and four foreground layers.
				Layers (all layers are identical):
					byte Tile Number
					byte Repository Number
					byte Flipped (bool)
					byte Luminosity (bool)
				For the mathematically challenged, 9*4 = 36 bytes per tile.

		ACTOR HEADER:
			dword Number of actors
			dword unused (0?)

		ACTORS:
			next 'sizeof(actor) (which is also 36 bytes) * Number of actors': The entire map's actor list.

			Individual Actor:
		        	dword ActorID; //civilians have one ID, soldiers another, etc
			        dword coord_X; //positon in the map
		        	dword coord_Y;
		        	dword Direction; //left and right.  Doesn't matter for most actors.
			        dword Type; //Distinguishes actors which have the same ID.  Terminals have the same ID, but there's a small terminal and a large one for instance.
				dword MatchID; //It's important.  Ask a mapper why though.
				dword SubPlane; //Ask a mapper about this too.
				dword unknown; //Believed to be a junk value.
				dword SecurityID; //Enumerated.  Refers to what security level actors appear on.

			The designer can clue you in to most of the vaues.

		PLATFORM HEADER:
			dword Number of platforms
			dword unused (0?)

		PLATFORMS:
			next 'sizeof(platform) (which is 24 bytes) * Number of platforms': The entire map's platform list.

			Individual Platform:
				dword X1; //rectangle coords
				dword Y1;
				dword X2;
				dword Y2;
				dword type1; //type1 and type2 are linked together to create what we NORMALLY think of as the platform type.
				dword type2;

				The platform IDs we're used to seeing, and the coresponding TYPE1,2:
					0,0 == PLATFORM
					1,0 == LADDER
					0,1 == STAIRS UP
					0,2 == STAIRS DOWN
					2,0 == TRACK
					3,0 == OUTSIDE ROOM
					3,2 == SPECIFIC ROOM
			

I think that describes the Silencer map format pretty well, though older map formats might not work.  To see it in action, view the code.