I have the same problem, and it happens on 32 and on 64 bit. I tried it with my graphics turned down the lowest settings, and it seems to work. I think the crash caused by the portal spawning, so it might be an effect causing the crash.
"Your courage... your power... are not completely insignificant. Perhaps you can be made to serve. Do not fight. Do not resist. Give yourselves over now, or be destroyed."