I also get the bug where masters do not show up in the tavern. The game tells me that the secondary mission is completed, and that new skills are available at the tavern, but when I go to the workshop, it tells me that I have not found the master yet.
Wow, this game is great, one of the best I have played in some time. I just finished it twice with different characters, and I am very much looking forward to playing the sequel. :)
Did not work well - lagged badly when it was trying to load, after a few minutes without any kind of menu or such appearing I gave up and posted this comment instead.
 "Decision:Medieval"){kind=icon}
 "Legend of the Void"){kind=icon}
 "Bubble Tanks 3"){kind=icon}