So Helm, the mock-up made me dump Photoshop and grab Promotion for the auto-tile completions stuff. And I read the manual and could not find much about that mode. So I took matters into my own hands, slowed down your video and wrote a page for my personal manual. I hope nobody minds if I share it, as this is the promotion feature that excited me most. Please forgive spelling and grammar errors or outright lies. Also, sorry for no visuals, but Helm's video should provide you with a reference for what is happening, since this is in part a transcript of what he did.
Using Cosmigo Promotion's Auto-Tile Completion Feature
In Promotion's auto-tile completion mode any grid tile that is identical to another when in this mode will be edited simultaneously. This is much like the tile-painting mode but vastly more powerful. If used properly, this will effectively give you a map drawn with a set of tiles instead of one giant image. Finally, using the Tile Map Export plug-in, you can then take this a step further for one-and-done game map development.
*****Some useful shortcuts to know for this*****
Fill brush with single color:
Shift-D
Show/Hide zoom grid:
Alt-G
Turn on/off Auto Tile Complete:
Ctrl-A
*****How to*****
Part 1. Set-up and display your Zoom Grid
Options>>Zoom Grid>>Adjust Zoom Grid...
The bottom two radio buttons should be checked, use the settings for the tile size that you would like best. Keep in mind your project frame has to be a multiple of the zoom grid size, so make sure you can fit an whole number of tiles in your image.
Select Options>>Zoom Grid>>Show Zoom Grid OR Alt-G
Part 2. Mock in your tiles
Using the Get (animated) brush marquee (The tool that looks like a dotted-line box with scissors. Make a selection that is the full size of one tile. You will notice it automatically switches you to the Paint Dotted Tool. You are going to use this full-size brush to mock-in your tile areas. Select a palette color and press Shift-D to change your brush to that color.
Now mock in the areas that you want to use the same tile. Remember, the areas must stay within the constraints of the zoom grid boxes, and must be identical. When you are done, you may switch colors, Shift-D to apply the color to this brush, and draw what will indicate other tiles.
When you have roughed in all of your tile areas you can proceed to actually use Auto-Tile Completion.
Part 3.
Press Ctrl-A to turn on auto-tile-completion. Edit your tiles. You will notice that tiles that are identical are being edited at the same time. At anytime you can turn off auto-tile-completion and add more areas, or change individual tiles so that they are no longer the same, doing this will take them out of the tile-group they are currently in when you reenter auto-tile-completion mode.
Part 4.
Export using the free Tile Map Export plug-in.
NOTE: When I was using it I was having trouble using any tool other than the basic brush tool. but working at tile scale it did not seem like an issue.
I hope that helps!