I've gone all the way through the game a couple of times, but I've never been able to solve the following:
1. City of Souls - I 've chosen the Mountain Crystal Golem to take out the gargoyles but then I can't get by the Towers or open the other gate after defeating the medusa creatures.
2. the 4th bank seal - I've found three: one in the Empyria gardens, one in Kathai and one in another place I've forgotten.
3. How to punish the goblin thieves in the Burning Mounds. I can't move on to the Collesium, etc.
4. (the big one) I haven't been able to figure out most of the puzzles, etc. in the Clockwork Crypts. I end up just killing that Kathai contrarian and going on without ever getting into the crypts proper.
I know that especally the last one may require quite a bit of explaining - if info. trickles in over a period of time or I get parts from different people, that's great. Any help would be appreciated as I'll be giving up this game soon, but I just wanted to get the full experience.
Thanks!

here we go as far as i can remember :

you have this one - Dryades Cove empyria
you have it as well Kathai
City of Souls
Blazing stones with the vulcano

As for the puzzles please find the detailed solution attached *spoiler alert*
I got it from a forum once but i don't remember which one. So the credit goes to the unknown forgotten creator :)

the goblin thieves i can't recall , are you talking about the races?
I just kept taking the same group (green). They won finally after 5 reloads :)


As for your city of souls question : did you already kill the gnome?


hope this was helpfull.
Late
but helpfull :)