The three books on Steam will eventually be three different products. Because I like to share as I develop, I put Book 2 on the Beta branch of Book 1, so everyone who has a Book 1 steam key also has a Book 2 steam key. I'm doing the same on Book 3, so it currently exists on Book 2's Steam Beta (as well as a standalone download here). To play Book 2 on your Steam Key, just opt into the Beta branch, and it's there and complete.
I'm still not 100% sure what the final solution there is... Steam's pretty strict about selling the game on other platforms for less than what it's sold for on Steam (to the point of terminating your account); if I give away both Book 1 and Book 2 steam keys for $15 I'm basically undercutting them by 50%, not something they'll take with any kind of good grace if they find out. I don't want to raise the price to $30, and it's kinda late in the day to do it as 3 different products.
I know most users don't care, and honestly if I hadn't given away a Steam key it would be a none-issue, so maybe the solution is to remove that. You still have access to books 1-3 here on Itch.io, so maybe that's the 'most fair' option. As always, it's fun trying to balance this between platforms, especially if your personal goal is to have everyone share stuff as soon as possible.
Itch.io has several downloads; book 1, 2, and 3 are different downloads. You can download them straight from here.
These are the compete versions of Book 1 and 2, and the first Act and Act+ of Book 3 (the rest of Book 3 will be uploaded here as it's getting done). I wouldn't worry TOO much about the version number on Book 1; the steam build got some steam specific fixes after release (dealing with steam specific issues, like achievements); it was content complete at 1.0, and if anything was actually broken I'd upload another build here.
