Another player and I are also experiencing this issue:
https://forums.larian.com/ubbthreads.php?ubb=showflat&Number=902942#Post902942

I've been working on another campaign while I wait for a fix, but it sounds like they tried loading an earlier save and are still having trouble getting into Act 2.

I found it curious that both me and the other player experiencing this are playing Dark Urge, so it makes me wonder if it's conflicting with a story cutscene or something. Are you playing Dark Urge as well or was it just coincidence?