Just at the exit to Cragswallow after fighting the dwarven automoton and picking up Grimsever for the queen there is a little room to the left with a dwarven device that can be activated but it says I don't have the necessary item. I have looked everywhere but can't find any key or anything - does anyone know what I am missing?

Thanks

It's from the main questline

cool cheers, saves me scouting the dungeons 10 more times