I've had a pretty hard time to install Baldur's Gate 2, even via PlayOnLinux. The problem lies when you need to change CD-s: PlayOnLinux do try to solve it for you, but it does not work.
But what works is multiple mounting. Awful and dangerous, but works:
sudo mount -o loop /path/to/ISO/CD1 /mnt
Start PlayOnLinux, select
mnt as CD source... and step through the offering to change CDs for you. When the game asks for the next CD, do the following:
sudo mount -o loop /path/to/ISO/CD2 /mnt
This will not unmount CD1, but at the same point CD2 will be accessible. Repeat this for CD3 and CD4. When the game asks for CD1:
sudo umount /dev/loop3 sudo umount /dev/loop2 sudo umount /dev/loop1
But don't remove
loop0! That's CD1.
Done, play Baldur's Gate 2 on Linux.