Managed to unlock plant lady (Yvaine's sister)...but I'm missing the two before her, one I think is Byron. Where are they found?

Even on the easier difficulty settings, the game, particularly boss fights is too difficult. The main issue is stun locking and recover times. Even the easiest bosses can easily trap you against a wall and then stun lock you over and over again, and the recovery time for many attacks is so long that you just sit there and get pummeled. It feels really unfair and frustrating. It's not the bosses health or anything, and I found this to be an issue on the hardest difficulty as well as the easiest difficulty...

We smashed his head, we hit his wound. Then he becomes insensible to our attacks. We managed to remove 1/6 of his health bar. I think the head is supposed to regrow, but nothing happens...

Unless it's supposed to take more than a couple of minutes to launch (and there's no way that's reasonable), the demo is not launchable for me (although the Steam overlay pop-up and some other pop-up popped up just fine, and the game did not prevent minimising its window to close it). Win7 if it matters....

I've still only got the first two characters, and I seem to be stuck because I can't unlock the guy with the whip, and also whomever can pass through the purple energy barriers. I've only got the first two characters, Elgar and Yvaine. I've been going back through older levels, and I just can't figure out how to unlock any more....