Glad your horse is ok.
Regarding Diva and her spilling the bucket... have you considered milking into a hand held smaller container and then pouring that into the bucket which is not in harm's way? If you are milking two handed to get both sides at the same time what I suggest certainly would slow you down... but on the third hand you would have the milk.... but then on the fourth hand I've had my goaties, darlings that they are, manage to put a hoof in the hand held smaller container. Frustrating to be sure but the majority of the milk is saved.
Let us know what you do regarding Diva. Could be she just needs to wrap her head around the fact she is going to be milked, period.