I just recently discovered that there are mods that actually add even more flavour to BG2. I quickly downloaded Teshia mod and Imoen Romance.

However, I was currently romancing Jaheira in my ragtag group. Doesn't seem to stop Imoen, though :o

So here's my question: what will eventually happen between those three ?

1) Is there some kind of built-in code that will turn my party into a cat-fight ? That was the bioware way (you couldn't romance two girls at once)
2) Do the mods simply ignore the fact that I'm romancing other people and doesn't adjust to it ?
3) Do the mods have a code that can recognize that I'm currently romancing someone and prevent the NPC (Imoen, Tashia) from becoming a love interest ?

Anyway, what happens ?

I'm pretty sure the Tashia mod has checks to ensure that the PC is with her alone. As for Imoen, it probably does as well, but I don't know for certain.

The Imoen romance also has checks for other romances. Both Imoen and Tashia don't get catty, they just stop the lovetalks once you reach the committed stage with Jaheira. Imoen has quite a bit to say even when you're not in a romance, though, so it might seem like the relationship is still active even when it isn't.

But do we actually get a choice at some point in the discussion ? If I wish to romance Tashia, for instance, do I have to actually chose a "bad" answer for Jaheira (like "bug off, you filthy tree-hugger lest I bite your leg off" ?)

With Tashia; yes, you need to tell Jaheira to knock it off. Alternatively, you could just use the CLUAConsole (or flirtpacks if you have them installed) if you don't want to be mean. With Imoen, talk to Jaheira after the second Imoen dream, and there's a nice dialogue option to tell Jaheira you're not interested.