I had the same experience.
my path was different;
~/Desktop/nand2tetris/tools/HardwareSimulator.sh &
This worked for the other applications as well, just change the app name, I.E. "HardwareSimulator.sh" becomes "Assembler.sh" or "VMEmulator.sh" etc.
hope that helps others.
Mike
Mike Pett
"Dads learn to care for babies the same way new mothers do –– with hands-on experimentation." Attachment Parenting Book - Chapter 12 Attachment Fathering - DR. William Sears and Martha Sears R.N.