The Raycasting Game Maker is a free easy to use game editor that creates simple raycasting games in the style of Wolf3D. The finished game needs only two files to run, an executable and a pak file with the game data. The game runs in Windowed- or Fullscreen Mode and supports 16 and 32 bit color.
Just an update found on the creator's site. The new v5 of RGM uses updated texture/sprite resolution of 128x128 rather than 64x64. The v5 download should now be up but does not support game files created in any version below v5 including v4.xx.
This image shows the difference between 64/128px textures in the engine.