So, the game installed just fine - but it wouldn't open. I did what anyone would do, which is to open the game through the terminal, figuring the errors thrown might get me further.

I was correct!

This is my first post, so I have no idea how to format any of this. If you want to install Baldur's Gate II on a newer Ubuntu-flavored distro, you'll need to do the following:

Make the .sh executable and install the game by running the file from the terminal.

Keep the terminal open and enter:

wget (see below) archive.ubuntu.com/ubuntu/pool/main/o/openssl1.0/libssl1.0.0_1.0.2n-1ubuntu5.13_amd64.deb

I suspect I can't post because it contains a link. So, be sure to turn that into a link.

When that's done downloading, run this command:

sudo apt install ./libssl1.0.0_1.0.2n-1ubuntu5.13_amd64.deb

That's it. That's all you should need to do.