Login with the new version, click 'Create World' and a persistent world server is created for you. Once connected, F10 takes you to the world editor where you can tweak vehicle settings, define game rules, move trees about, paint your landscape, etc etc.
A video demonstrating the new system can be found in the video section.
Also in this release are a number of additions and improvements to the in-game 'World Editor', including 'live' texture swaps and improved settings screens, as well as the usual array of new scripting tools and content. A few bug-fixes and price tweaks are included for space.
You can download the latest version free from indieDB or the game's website at Theuniversal.net