I think that a line indicating the proper shell needs to be added to the top of the Unix/Mac shell script in the manual installation of Vassal. Without a specified shell, the script will run in whatever shell the user has chosen and if that isn't Bourne/Bash, then the script will fail.
Adding the line #! /bin/sh to the top of the VASSAL.sh file will specify the script. I find it's usually a good idea to put a space after the "sh" just in case the script gets saved in DOS format, so that the CR isn't read as part of the shell name. -Tom.
