The source diskette was part of a household collection and may contain e.g. high score files that were not present on the original pristine filesystem. Check timestamps: any file dated 1990-01-01 or later, that isn't mentioned in help.doc, is likely not original.
The file dosbox.conf in the zip file is not original. Its purpose is to slow down emulation.
@echo try one of these commands: "FRIGATE" "MAZE1"
MicroCom Systems Reference Collection (c) 1989, all rights reserved.