The variables are the two environmental ones needed to be set for LTC mining (they are the first two lines in the bat file)
setx GPU_MAX_ALLOC_PERCENT 100
setx GPU_USE_SYNC_OBJECTS 1
Just FYI, those 2 settings are permanent don't need to run them every time.
Really? I would have thought the scope would have been within the Dos Box lifetimne, or at the very most until a reboot. That is worrying.