Stacking tool issues

[LogGits]

Paper 561, StackMob 3.3.3.

Issue: stacking tool "split one" mode doesn't allow me to set a value below the value of the entity. E.g. if it's 10 cows stacked and i type 0-9 it doesn't work.

EDIT: Upon further inspection, it appears not to update the value of how many entities are in the stack. When i killed the stack of 10 cows with a sword (2-3 hits) the whole thing dies.