Playing Avernum 6 for the first time, enjoying it.
I've accumulated a few piercing crystals and tinker's crystals. I could run all over the world and cheat with quicksaves to figure out the best places to use them, but it's quicker to just ask here.
I have done 2/3 of Meryhew's original quests, also been sent to the portal/portal tower and completed events with Nichols there. The lower left quadrant is fairly well explored.
Any suggestions on what doors and barriers to open? I'm playing with the default party, just with characters renamed, if that makes a difference.
Also, and not looking for detailed spoilers here, but should I have gotten any clues by now on where Treviass is? That's the Meryhew quest I haven't really even scratched yet. I'm assuming I just need to wait, but maybe I missed something.