Crytek recommends using a 64-bit computer for production work with Sandbox.
On a 64-bit PC, CRYENGINE Sandbox can be started by running the Editor.exe application found in the Bin64
directory.
If you are using the source code, the Getting Started with Engine Code is an important document for you to read.
As of CRYENGINE 3.6, only the 64-bit Editor is supported.
It is also possible to run the Sandbox Editor in 32-bit mode, by starting the Editor.exe application from the Bin32
directory.
The 32-bit version is just provided as-is without any further support by Crytek. Using the 32-bit version of Sandbox might result in the application crashing when doing a lot of editing work on a level.
When you start the Sandbox Editor, after initial load, you'll be greeted with a welcome screen. This screen will give you a few options on what you can do next: