Got a huge IDCS6 file from a client today. The text was linked to a Word file, which the designer didn't include. I tried unlinking it but CS6 froze. I then did a Save As, tried again, and it froze. Tried exporting to IDML, opening that, trying again, and it still froze. Then I tried opening the IDML file in CS5. The text file unlinked flawlessly and I was able to save as an IDCS5 file, open it in CS6, and it was smooth sailing from there.