Steam base vs normal expansion compatibility issue

My husband was gifted The Ultimate Abyssea collection a while ago via Steam, and it took a good half a day to install it all. He's just bought a normal version of the Seekers of Adoulin (which wasn't labelled if it was compatible or not with Steam) and it was requesting him to uninstall POL, and so he clicked ok and it crashed saying POL wasn't installed. I know about the compatibility issues but is there anything that can be done so he can install the SoA expansion pack without having to buy a whole new game again?

Ah nvm, he found a lengthy post somewhere in these forums which explained where to find a setup.exe within the install files to install it since the installer itself isn't compatible with Steam.

This is where I found the workaround - basically the installer is completely broken and this fixes it:

http://forum.square-enix.com/ffxi/th...nix-EU-shop-DL