Solved!!!!! I think this is a defect that should be addressed by the LinuxCNC community.
Tearing my hair out, but here is what I did.
Went into the file, and the Gcode files all had a % symbol in the start, and a % symbol in the end. This did not result in any error being displayed anywhere on the screen, and these files ran without a hitch. But it would kill the HAL button with file attached, which is the Z Touch button, with the error "Otoolchanged not found before EOF" when I hit the button.
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Exactly the same problem is with latest pre 2.8 and the gmoccapy on_abort script. It will only function if I remove the '%' signs in the on_abort.ngc file.