if you want to protect mesh which colored weight map,
select mesh by pogion group editor,,or using group selection, or with lasso, selection, ,,each mode waht you want.
then change tool to weight map brush,,
from tool tab menu>poligon rocking>Lock selected.
it protect your mesh weight color changed.
(you can not add any weight map for the mesh)
then,, if you want to protect weight map which colored for each node,,
in weight-map brush tool,, go under, Locking tab .
then select the node which you want to keep the wieght maps and rock the node.
in my test,, it can protect weight color for the node.
if you colored weight for bone1 x rotaiton 0.7 or 0.8 about one vertices, then Lock the bone1,
you can not fill color weight 1.0 for bone2 xrotation about same vertices which have already colored the weight by bone1 xroatiton.
it seems keep the all weight value for bone1. (you can check weight value of each vertices which selected,,
by selection Analasys tab)
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