TW p137 gives us the rules for utilizing MASC. If a mech fails a MASC roll, one crit is automatically applied to each leg. so far no problems.
is the crit random, ie 4 actuators + 2 jump jets, roll 1D6 and possibly destroy a jump jet ( get out of jail free scenario ), or is it limited to the actuators only, ie 1D4 or is it predetermined like the super charger. i.e. start at the top and work your way down ?