I've got a layout where I put the sprite pieces to my bosses of my game in. The sprite pieces have a few frames each. I make sure that they work well with the boss and then once that's done I cut and paste them to what I call the BossPiecesLayout, just so I feel organized. Every boss that I cut and paste the pieces into the layout, Memory Use Increases by about 4mb. Why is this? How concerned should I be? What will this do?
If by increase by 4mb you mean the "memory use" indicator at the bottom increases, then I think it tells you that basically the layout that in theory uses the most memory will be using that much, if said layout is just a "dummy" layout with all bosses in (seems like it as it increases when this layout increases), then it is not as concerning as said layout won't be used in game.
Still can be a bother as the indicator kind of lose its purpose.