I've been trying to get some friends updated with HD mod(which I found some topics saying it does work with this), and the issue is we are all on different OS's.

Getting this to work on MAC(for my brother)seems to be the only problem at this point. I'm wondering if the GOG version has updated the openal library to a modern version or if it is using the openal32(which Apple no longer offers in it's repos). I would consider buying this from GOG if I knew it could solve this problem.

https://forums.linuxmint.com/viewtopic.php?f=225&t=239372&p=1284845&hilit=diablo#p1284845

This link shows my journey(Zeddrich)getting Diablo to work on linuxmint, this method should also make Diablo playable for ubuntu users. Although I can't confirm this method will work with the GOG version, but I wanted to share this for anyone hoping to run this under linux.

I got the Beezlebub mod working perfectly on OSX, but I had to update openAL myself. The GoG version doesn't have the updated OpenAL.

I'm curious did you have to compile it yourself from source? If not, can you please provide the link for me.

Check out https://github.com/diasurgical/devilutionX it's a native Linux port, and there's a Mac version in the works.

I used a Wine wrapper. You can use PlayOnMac or Crossover too. You have to update openAL through the Wine wrapper or you get an error. It runs much better than trying to run vanilla Diablo through Wine, even after trying the various DX fixes.