I believe the mod is 'Your Seedy Hideout' by Marac, and it's no longer available to download anywhere after PES went down. The wayback machine doesn't seem to have the file either--or at least won't let me download it. I remember it's a mod that adds a sort of gothic styled little house in the vivec sewers, not the most purist friendly but I enjoyed the aesthetic nonetheless. There was a phonograph that when activated would play a song--and I can't for the life of me remember anything about it beyond the fact that I liked it. I have no idea where to start looking, honestly.
And honestly I also have some questions regarding commissioning mods and the like (mainly 'is that a thing that's legal/would people be interested in payment to make specific mods')--but I'm not sure if that would be best saved for a separate thread and... im not entirely certain which board would be the best place to post it, whoops. I've been visiting this site for years but never actually participated in the forum--so i apologize for any mistakes on my part!