Yes, it should. (Why are you using 98 may I ask?).

As per the FAQ, I'd suggest using Rebirth with it as well.

Er, how do I enable music with the sourceport?

Thanks.

Will the Add-on tracks mesh properly? The MIDI stuff is awful compared to the actual music.

The Add-ons are the original music that came with the game :) So yes lol

Truthat. Just worried that the game emulator might not recognize the format and play them out of order/not appropriately etc.

Sorry I'm just now responding to this, but to clear up the confusion, the AddOn packs have a file built-in that tells Rebirth what order to play the tracks, so it will always play in the order intended :)

Descent Rebirth is fantastic! Thanks for the recommendation :)

You're welcome! :)

Can anyone post a link to where to buy this on GOG? I have searched and only find Descent: Freespace Battle Pack....

Edit: I found the thread noting that they were removed from the catalog. I was lucky tonight though because I found a copy on Amazon of the original game. So I can at least try to get that working on Windows 10 with the DXX and other 3rd party packs. Failing that, I will try setting up a linux machine with wine, as I have read that it works great on there.

Using the installer linked in this FAQ will work fine on Windows :)

When did it disappear from the catalog, and is it coming back?

It disappeared a few months ago now. It doesn't seem likely at this point that it will be coming back.

Can someone please tell me about Descent level types: normal vs. anarchy. What's the difference? Why I can load anarchy levels only through Multiplayer and some of them (if not all) have the reactor core as well.

Anarchy Levels where designed for MP play.