The meteor is part of the background plot, but aside from a couple medium crystals there you don't do anything with it.
There is no other purpose to the strange gems.
In the south east of the lich cave, there is one fixed statue in the centre of a pentagram, with 4 other pentagrams on the floor....
<span class='standouttext'>Spoiler : </span><span class='spoiler'>Place the 3 statues on the 3 outer pentagrams, and a key will appear in the centre.</span>
Killing the 3 liches which are not the master have a profound effect on the loot you can get, but that is it (can also use Pickpocket for this).
Opening the box is a permanent effect, and results in a couple comments by various NPCs, but that's it.
If you had run past the fire elementals and blew out the 4 strange candles, a fire elemental would have died for each (though you do not get experience that way).
Leave one character at the hermit's cave (etc) and stand by the trapped cocoon with the other. Pause the game and open the cocoon, then switch to the other character and enter the hermit's cave to teleport the other character away from the trap.
