Code:
xc3sprog c cm1 p 0 Ixc6lx150.bit twin_test.bit
does not work, but this time it's complaning about a filename issue to me. My initial hunch is that since the board im punishing is #108 the firmware filename on it has changed along the way. I'll re-read up on this , of how I wsh the search function on this forum worked better 
.. but for now Im going with the temporary flash.Strange...
When you type a "ls -l" do you see the files in the directory? And make sure you use the correct filename, the filename in UPPERCASE is XC6LX150.bit, I did a typo the first times, so I used xc61 (number one here! but it is a small "L")...
Here is my directory (ls -l) after copy the files from usb stick:
If you have the same, the commandline should work.
good luck!