I've got close to the end (I think) The Witches are all standing around the summoning pentegon, they tell me to stand to the side, but nothing ever happens.
Is there a specific spot I have to stand on?
I've tried reloading the save from just before.

Is this just another bug or is there a walkthrough so I can see what is supposed to happen?

Hi, I know I'm a bit late on this... but yeah, there is a trigger you first have to stand on, then you have to move away from the coven. If it still doesn't work, just reload and try again (I know, it's a pain!)

I have written a detailed walkthrough starting here:

<span class="bold">Exile of the West - Part I</span>

All three endings are covered, plus the bugs, oddities and stupid things I found. I have some unsolved mysteries, though: they are listed at the bottom of the link.