Scroll down and download the file for your platform from the Assets section. To build applications using the engine, you should also download Lazarus (which includes FPC) for the same platform. E.g. most Windows users want to download Lazarus for Win64, and CGE for Win64.
This is a "snapshot" release, automatically updated after every Castle Game Engine commit (if it passes some automatic tests). In practice, it is very stable, and some people even use it in "production" to develop games.
This snapshot release contains all the latest cool stuff described on Castle Game Engine News. The
bin/ subdirectory contains compiled executables for all our tools, including our Castle Game Engine Editor (
castle-editor) which provides an integrated environment to develop games (manage projects, design UI and scenes, build...).
If you upgrade from CGE 6.4, take a look at the "breaking changes" list.