What you MUSTN'T do to complete main quest

[JoyRide]

I was just wondering what things you cant do in order to complete the main quest, heard many managed to break it, for example reading something in the monastery, something about not going to Xardas too late/early, and something about not talking to the king... Would be thankful if you could clarify this, and maybe we could make a list

[Innos allmighty]

The second patch is supposed to remove this.
Trelis without it could be impossible to liberate. that ruined my lvl 60++ character. It was to late when i installed the second.

[JoyRide]

what did you do?