So the cat is out of the bag finally, please be aware that the new editor is heavily a work in progress, it is just for preview right now. The undo system works for some things but its not implemented for others, some tools might change their looks and workflows, the in-world clickable icons for the objects other than meshes are not yet in there, some tool actions might crash the game, for example object creation, we're still working on it, porting it from the (now) old editor . We're also trying new editing ideas, some might be discarded, others added. All in all, a lot of work done and to be done! Please bare with us while we nail down the features and bugs. Of course, suggestions are always welcomed, we can add them to a list and if makes sense and are good ideas, we will implement them. Thank you for your cooperation and understanding! PS: For Lua, we also have World Editor Coding section in the documentation, the editor has a lot of APIs and examples on how to use it, albeit I would refrain from now to use it to make tools for the editor because the APIs might change in the next months, but most of it will stay as is, you can check it out to learn about the paradigms we employ in the new editor.