there is a package available upstream for both cosmic and bionic, would it be possible to maybe fix the script to not add the broken repo for cosmic?
The repo is mainained by the FS-UAE author and it's the recommended way to install it (https://fs-uae.net/download#ubuntu). If anything changes regarding that, we can also update the script. While for 18.x the latest package is upstreamed (Ubuntu), for older releases the PPA has the latest version. Let's see what happens when 19.04 breaks loose.