Exit Quickly from Toolkit: Instead of exiting the Toolkit through the X button, you can instead go to File → Exit. This closes out Toolkit much faster.

Stop Picking Things Up: If you want to use an object as decor, you can check “disable interaction” In the sidebar to prevent people from looting it (good for flowers/herbs that are normally loot). See below:

Using Layers (aka folders) is super helpful to maintain organization under the World Outliner. You can Ctrl + Click multiple items and then move them into a "layer". Very helpful with keeping things organized. Select all building items (doors, windows, walls, etc) and move them into Constructions, for example. You can also make new layers. More than one building you're working on? Create a new layer in the World Outliner, rename it, et voila.

You can use a drawing tablet in the toolkit while making your map. It’s super helpful for precision during the terrain painting process.

Clearing level cache: when you edit vanilla levels and move objects around, the changes won’t reflect if you’ve already visited that level. In order to see those changes you need to clear level cache. It can be done via SE console by entering Osi.DeleteLevelCache('level name here') . For example Osi.DeleteLevelCache('CTY_Main_A') will delete cache for CTY_Main_A level (act 3 city) The command needs to be executed while being on a different level.

Rotating Groups You can select multiple items and rotate all of them at once. You can rotate them as a group (e.g., if you build a house and put things in it, you can select the house and everything in it and rotate the entire house) or you can rotate them individually (each item will rotate on its own axis, it will not change position but will just rotate in place). There’s are some parameters in the bottom bar that you can toggle.

Photo Mode: You can access Photo Mode via the Game/Live Mode in the Toolkit. Make sure you EXIT Photo Mode before switching back to Editor Mode, as the Toolkit will lock you out, and you will need to restart.

You can add items to your map by dragging and dropping them from the Root Templates menu. (You will see a preview of the item so you know where to place it — if you don’t see this, right-click on the Create Object button to open the Interaction Mode Options and make sure “Show Preview” is checked. You can also change the color of the preview in this menu.)

No Terrain Selection: In Select Interaction Mode uncheck Terrain, so the selection box doesn’t select terrain. You can also uncheck some more stuff.