Magicavoxel Color Palete?

I have been trying to merge models through magica voxel so I can make containers for certain items, and to fit certain things to hearthling models.

Is there a universal Stonehearth color palete that includes all current model colors? Magica voxel doesnt seem to like merging models, because every time I try to paste voxels from a model to another, the colros disapear and it uses the ones from the initial imported model. Is there a way of setting it up to it always keeps adding the colors from whatever models we like? like what voxelshop does?