Are the puzzle-focused dungeons part of the main quest (you cannot advance the story unless they are solved), or are they side quests? Thanks.

Against my better judgement (I didn't continue with the predecessor because of the terrible lighting in the dungeons), but then I started the second part. Now, when you get to the point where you're supposed to find the guy west of Mirokynos Tower, there's a problem. If you talk to the guard directly, the game freezes when you enter the tower, and that's it. Only when I ran to the gate and spoke to him did a pop-up for a new quest appear, and I was able to enter the tower. I dunno if I am the only one w...

Wondering how replayable is this game. Also how long it is? Finally, any chance for a bit bigger discount for an owner of the previous game by purchasing it as a bundle and to encourage players to get both games for the best price?