I was profoundly disappointed to learn that BASS is a ScummVM game, and thus, not importable into Boxer (a fantastic DOS emulator on the Mac) on the reasons of non-antialiasing (I like the blocky pixels, rather than fuzzy ones) and speed control (I think it would be better if characters weren't moving their mouths like chipmunks on LSD). Any way I could do this?

For the first request just configure ScummVM about not using any scaling.

About the second I do not even understand what do you need; ScummVM gives the correct speed. And I am fairly sure ScummVM has been ported to your system.

Although it was a GOG.com freebie, I can't understand why they didn't include the original EXE. It's just that I prefer Boxer, that's all.

Actually, I probably don't need to have my question answered: is the version on GOG the same one as the version on the SCUMMVM site?

Yes but i think that scummvm is more updated since this version wich gog provided has a game brealing bug.

Revolution Software released Beneath a Steel Sky as freeware some time back. You can find the files from the original DOS CD and Floppy Disks at:
http://www.classicdosgames.com/game/Beneath_a_Steel_Sky.html

Also, look into my entry on the Community Wishlist:
http://www.gog.com/en/wishlist/site/images_of_original_installation_media

I too wish the original .exe was included for the fiddlers among us. A number of .conf files that GOG makes, for example, tend to use "Soundblaster 16" for the MIDI, when "General MIDI" would produce much better sounding sound, for those of us with better sound cards at least, so being able to tweak things is a must for me.