Compiling the source code
From Platinum Arts Sandbox Free 3D Game Maker
Compiling the source code
Windows:
Main Method: Click here to download the version of Codeblocks with the mingw compiler: [1]
Then go into your /src/mingw folder. Click on sandbox.cbp and codeblocks should load up. Go to build and then build and it should create the Windows binary :)
Other Methods: There is a visual C++ project file included that you can use. Load up the proper file and compile :) I'm not sure if you'd need any libraries but you probably shouldn't need any.
Linux and Mac: The linux makefile and mac xcode folders are included in /src/ Use the proper tools to launch those project files and compile away.