Winter ring/guard amulet issue

[M13908]

I am currently trying to complete the puzzle to get the winter ring, however I'm quite stuck. I eventually looked up how to do it, but it seems all the information about it is old, or possibly changed, that or I have run into a bug.

There is currently only a single panel I can step on, which removes the lava from the other side, however I do not see any of the other panels I am supposedly meant to step on to either lower the gate to the lever, or open the gates to the chest.

[VillaNZ]

It has changed since the original. First place a heavy weight on the pressure panel on the left hand side (as you noted). This will clear the lava on the right side. Have someone sneak or float past the sentinel on the right side (note I found Winged Feet really useful); there is a lever behind the sentinel. This opens the gates on the left hand side to access the lever which finally opens the gate to the chest.

Having said that, I had already acquired the Winter Ring through telekenisis in the treasure room (although I suspect that was bug). Still worth completing for 5k XP.

[Duflax]

I just killed the sentinel from range with my wizards wand.