Thanks so far.
Unfortunately, setting 'm_no_interrupt' does not convince CPUID that everything is correct
When the trap flag is set, an interrupt occurs (and the state of 'no_interrupt' does not matter then). I highlighted the relevant sections in I86.CPP and CPUID.ASM.
dec cx is never executed in our present code.
CPU-ID 1.38 (DOS; COM binary for 8088 compatibles)https://dl.dropboxusercontent.com/u/37819653/BANNISTER/CPU.COM