Unity's 6.1 new auto tile map editor tools and new tile set system questions

Was wondering if someone could give a little more information about the Tile Template creation process for the new auto tiles and rule tiles.

I figured out how to create new tile palettes using the new Tile Set asset tool, which is a huge upgrade to Unity’s Tile map tools in many ways. The main thing I am having issues with is some of the auto tile/rule settings on the new editor window for creating tile templates.

Could we get some more information on the differences between mask 2x2 and mask 3x3?

Also, some information about the options we have when paining the auto tile rules when creating the tile template asset itself mainly the part where you paint the red mask in the new editor tool.

Just note even without the auto tile editor the other new features for tile map like the tile set asset is a huge upgrade in many ways, so thank you for that.