Story-wise, I believe you'll be fine, but don't install Additional Encounteres, it's cheesy(Bodhi encounter especially).
Technically, it works fine for most people and it's one of our most popular mods. I recall there were some issues, as the mod's maintainers been away for quite a while, but generally it's a safe small mod.
Please, read this thread about clean backup:
http://forums.pocketplane.net/index.php?topic=17555Generally, I recommend backuping dialog.tlk, chitin.key, bgmain.exe, baldur.exe and your entire override folder before installing ANY mods.
And check out our other mods.
I recommend Banter Pack if you want a more or less seamless experience.
Also, check these communities:
http://forums.gibberlings3.net/ (BG2 Tweak Pack is one of the best mods out there, and if you install EasyTutu(see
www.pocketplane.net/tutu and go to EasyTutu page from there), BG1 NPC is a good mod to have)
http://www.shsforums.net/index - various mods. Really various mods, but recently released Imoen's Friendship, for example, felt like it should've been in the game from the very beginning.