Just drag and drop the leaders onto to top part of the player board (should snap).

Not working for me either. I've dragged leader boards to the top of player boards but it's just not registering.

Months late, but I had also some trouble getting started at first.

Assign yourself to one of the four player colors (by clicking your name in the upper right corner). On the top part of the player board is a spot where the player card IDs will snap when you drag and drop. Do that for yourself and two automata. Then begin your game. This mod will ask you which colors are automata; select the two colors you placed ID cards.

Late to the party on this one, but @fucoxanthin is correct. You have to choose the Hotseat mode, not select a seat yet, load the mod, change your color to one of the available seats and then TTS will cycle through the remaining players to select their respective seats.

Once everyone is seated, it will pop-up the game selection screen, but just cancel out of it as the mod will have been loaded already in the previous step (i.e. prior to select seats).

After you go through the process a couple of times, it will be second nature.

I'm still having issues setting up a solo game despite the thorough instructions. The minimum number of players in hotseat mode is two, so the closest I've come to getting two Rivals/House Hagal working is by doing the following:

1) Choosing hotseat mode (selecting the 2 player minimum)
2) Cancelling out of color selection and selecting the game from the menu
3) Choosing my color
4) Cycling through other players' colors
5) Cancelling out when prompted to choose a game
5) Selecting the desired expansions (Rise of Ix, in this case)
6) Dragging player boards to their respective spots for myself and each player

Unfortunately, even then I end up with a two-player game with one Rival. Is there a workaround to the 2 player minimum for hotseat mode I'm missing? Anyone's assistance would be greatly appreciated.