Allocation Error with Multiple Cell Updates and USE_WEIGHTED_ALLOCATION
Making multiple updates to the same cell incorrectly spreads the updates to the children. The first time the parent cell is changed, the spreading is correct. If you then change the parent again, the spreading is wrong. For example, halving the parent's value does not halve the childrens' values when using USEWEIGHTEDALLOCATION.
Also, after the first update, NULL cubes are replaced with zeroed cells. That is, the children that should be NULL are now allocated a value of 0.