The door puzzles with lit nodes on the ground are a bit trying. It sure would be great if drawings with solutions were available. The written instructions are quite vague.

Shamans Path
https://www.powerpyx.com/wp-content/uploads/hzd-fw-sq-the-shamans-path-ourea-puzzle.jpg

Forge of Winter
https://www.powerpyx.com/wp-content/uploads/hzd-fw-sq-the-forge-of-winter-15-restore-puzzle.jpg

I could not find one for completely draining the water in Greycatch, but there are a couple of short videos on youtube.

And here is a screenshot for Greycatch. To finish the puzzle, rotate the last valve (at Gildun ) to face the generator.

great!

A problem with pre-written puzzle solutions is errors in number of turns.

The Grave Hoard entrance will not open.
I've talked to Ohtur, who guards his gates, and I destroyed machines in the valley, then his gates open. Never seen Rhavid, and Yariki was not at a small frozen lake. No one has given me the Frozen Wilds quest, therefore I cannot get into Grave Hoard to get one of the Power cells.

I think that's your answer - when you get that quest it will then be open.

I watched a video for the Makers End. After checking out all the data sources there, the hologram of Sylens told about Grave-Hoard. After a stopover in The Sun Shall Fall in Meridian, finally went to Grave-Hoard and the entrance looked like it had been blasted open. I strongly suspect there are several ways to open the entrance. The one that bugs me is someone posted that the final 3 power cells were at the large bandit camp to the far northeast, 2 being on the ground level just lying there and the final one in the far north side of the camp on the highest platform. Of course that was a crock of S!

Maybe the console version and pc version is abit different in that way? On what you said was a crock of S .. I mean honestly I have found that HZD had do to players finding thing never meant to be found.. getting parts of the game changed in upates to prevent trouble later on and other cases afew things removed fully do to finding such things .. for example a aera in I believe it was the console version someone got to a ledge that was left in the dev team that was unreachable by players or atleast seems they thought was unreachable by players if not so hard to that it wasn't worth removing that had what looked like a dead being that looked like it had been lets just say enjoying quite abit what little time it had left alive.. if you catch my drift .. So when word got arround enough the part of the game with that findable got altered as a result .. so maybe it was a older build that was posted about or the console version

those were quest items, not for collection and use by yourself. they were for Petra's cannon.