I have tried a form you described, and can confirm the values are not "propagated" Excel style. That is with Trigger Event: Change for E, F, G.
However, when I used Rule: Global, Trigger Event: Keyup it worked like charm (by using Tab key to switch field focus).
This is probably because trigger event Change to recalculate field values was not fired after the B/C change (is Filled). Only if I changed A or D the event fires.
P.S. It is fired, but before the values are filled, so that means both B and C are 0.
By the way, according to the brief instructions, if you fill a field with value, you are supposed to use is Filled, and when filling the value of another field you use is Filled By