Throne of Bhaal acting really weird

[Jelboo]

My Throne of Bhaal is acting reaaally weird. First, I thought it had something to do with the Kivan mod I'm playing. Normally you can initiate dialogue with him as the PC, but when chapter 8 starts, I can't anymore.

The problem is however that my singleplayer save seems to think it's a multiplayer save. When I kick someone from my party, I get a generic message that's the same for all of them instead of what these NPC's would really say. When I talk to them, they say "Hello there" to me with the voiceset of the commoner. That's what happens in a multiplayer save, right?

But worst of all, anytime during a dialogue with any character, whenever one of my NPC's would normally interject, the dialogue abruptly quits. So, yeah… I can only talk to Sarevok if there's no one else in my party. And I can't talk to Melissan, or anyone else that has a dialogue that would include a party member of mine.

Does anyone have a clue what's going on? I play this on a Mac, downloaded the latest patch and only have 3 mods. I would like to mention that Baldur's Gate has always been a frustrating ordeal for me - I love the game, but there's almost always something wrong with it. :/

[ElfBane]

Sorry I got to this late, but have you tried a save before the problems happened?

[Jelboo]

Well, since the problems arise immediately at the start of the expansion pack (in the forest with the talking statues), I tried loading my SoA final save to defeat Irenicus again and again, but it happened each time. The moment ToB starts, the game becomes weird. :/ The only way I could play without any problems if I played the game solo, at this point, so there'd be no party interactions at all.