I'm guessing no-one's figured out how to unpack it yet?
Unpacking the files should be fairly straightforward, but the format it is stored in is not standard MIDI format, as far as I can tell. You need the music files from the Windows version of TTD in order to be able to use them in OpenTTD, I'm afraid. There are sites on the web where you can download them, if need be.
-- Owen Rudgehttp://www.owenrudge.net/
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