Yeah I have been there the first time.I myself have not applied any mods, I don't know whether GOG modified it in any way. From what I can tell they packed mission packs, official and unofficial ones, in there too, which one can select in the in-game menu. There's one patch offered for download ...

I recently bought Descent 3 from GOG. I think I have at least two times if not more collected "quad laser", and on my left upper screen, just under GuideBot, it shows "quad laser". And I have the superlaser. Which only shoots 2 beams, not 4. I just watched a YT vid of someone playing D3 to see how ...