I'd like to see (or rather hear) the soundtrack, too. After a while listening to the music in your mind does get a little unsatisfying ;-)

I notice that there is a RESOURCE/MUSIC.RES file in the GOG-distributed Capitalism Plus installed directory.

It contains such tantalizing strings as "AMBIENT6" "VIPEWAY1", "TECHTRN4", and so forth.

Things that would seem to imply that MIDI is used here: XMIDFORM and XMIDTIMB, Seq-1, Piano, Bass, Strings, Bell, Snare, etc.

The file isn't recognized by Unix's file command, and doesn't start with a magic number that I recognize, nor do the MIDI file headers show up within the file.

Also, simply using a DosBox environment with MIDI configured and working is not sufficient for that music to play -- I configured one and tried running Capitalism Plus within it, without luck.

Since i was kinda pissed not having music in my CapPlus i decided to dive into the locker where i have all my game boxes stored and guess what i found? I found my original German DOS 5.0 version of Capitalism (without Plus) from 1994 (i think) with original CD!!

So i decided to try to install it on my Windows 7 64-bit system. Basically i did everything the same way that GOG did with CapPlus, that is: copy all CD files to a directory, copy CapPlus DosBox directory into this game directory, make some modifications to dosboxCapPlus.conf etc, create ISO image with Daemon Tools Lite of the original CD and put it in there (like GOG does with the image of CapPlus).

After doing that i had good old CAPITALISM running!!! But no sound and no music. Yet there is a SETSOUND.BAT in there and i tried to run it in DOSBOX (remove EXIT command at end of CAP.BAT so that DosBox stays active when Capitalism is terminated is the lazy way to have DosBox running in the command mode necessary).

SETSOUND.BAT starts 2 driver config utilities, one for sound effects and one for midi music in this DOS!!!!-Version of Capitalism. After providing the values necessary for both setup utilities (use brain and dosboxCapPlus.conf values) i actually had sound and MIDI MUSIC configured and my Capitalism is now running with both.

I noticed that the SETSOUND.BAT in capitalism plus only configures sound effects (SETD.EXE) but no midi device (that would be SETM.EXE). So i used the SETSOUND.BAT of Capitalism to configure also MIDI for CapPlus and the MIDI testsounds were playing correct in SETM.EXE using a generic MPU401 device!! But still CapPlus.EXE doesn't play any midi music, so the calls to the midi music must have been removed by good old Trevor Chan which seems a bit weird after having that stuff already work correct in the older DOS5.0 version of Capitalism.

Edit:

LOL to play CapPlus with MIDI i now just need to start my good old Capitalism in window mode and leave it in the background sitting in the menu while playing CapPlus.