DTD585:
I am no expert on the 225 aircraft or the Makila engines, but we do have them operating where I work. Talking with the engineers who do work on them told me.
If a negative torque margin the aircraft would be grounded until rectified.
This is not normal. Same as if you had normal torque margin and negative T5 margin would not be acceptable either. Both should be positive figures.
One interesting issue we had recently with this problem of negative torque margin and positive T5 , and also was on the #1 engine, after numerous torque system checks, engine swapped. Airbus finally agreed the problem was more then likely in the main module.
Replaced the MGB and torque margins back to normal readings.