There is no up to date list of bugs or known issues; there was a topic for the unpatched disk version (
QUESTBREAKERS AND MAKING DIV LIFE DIFFICULT), but later patches fixed most of the issues.
I don't think I've seen mention of a group of opponents switching alignment before, but there have been similar, though rare, issues in the disk version.
Hostile traps / summoned / resurrected creaturesA couple people with the download version have had specific friendly NPCs actually be hostile (which could be fixed by hex editing a file in the save folder).