I've been running some experiments with (mostly) BUILD games, in a laptop running MS-DOS 6.22.

I've (succesfully) copied/cleaned Duke Nukem 3D, Shadow Warrior, Blood, Redneck Rampage and Heroes of Might and Magic 2. The goal was cleaning (getting rid from all the stuff that Steam and GoG puts into the games to run them with dosbox and custom launchers) and avoiding the use of CDs or CD images. Also, I have a Dosbox folder in my Ryzen machine so I wanted that those games installed on that folder.

I had to use tppatch with some games (strange that Redneck Rampage Route 66 needed to be patched to run), but I've also had some minor issues/questions...

Duke Nukem 3D:
I've tried cleaning both Steam and GoG releases, but it always try to read from CD (showing the abort, retry, fail message). It's strange because it didn't leave data on the CD nor had CD audio tracks, and choosing fail allows the game to run. If D: does not exist (running from Dosbox without any CD mounted) or D: is not empty, that message doesn't show. Do anyone knows how avoid that message?

Heroes of Might and Magic 2:
I've made a .bat file that launches fakecd to mount a folder as a CD, then launch the game. On my real DOS machine, fakecd uses d: as the emulated drive and everything works fine; in Dosbox it uses A: (Heroes launch as multiplayer only). If I try to force it to use letter d, it complains about not having enough free letters and suggest to use lastdrive. I know that it's not a big deal because fakecd is only needed on real DOS machines (mounting the directory using mount -t iso works fine in dosbox) , but I'd like to use the same .bat file for both machines.

Alternate question... how can I know from a .bat file if it's running from dosbox?

Blood:
I've copied the game and worked fine (without CD sound or movies). Then, I've copied the movie folder from the GoG image and modified blood.ini and made the game show the movies. But I've noticed that there are two versions of the same movies stored on that folder, one as an AVI file and other as SMK/WAV files. Do I need those AVI files? I guess that they're only needed for Windows versions of the game, and they are wasting some 100 mb.