This has to be run in Cabbage, obviously, with the GM_test.txt file in 
the same dir as the csd.

I could also make a csound only version displaying the problem.

The error I get

INIT ERROR in instr 11 (opcode strtodk) line 78: strtodk: empty string
  from file /Users/richard/Desktop/ESMS/csds/chnget.csd (1)

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