Here, you touch at the concept chosen
With the opening and closing of containers that allows to have the tabs or the ScrollArea progressbar fully operational, using the real Gadgets.
But, in fact, it requires some processing:
. to deactivate the previous level, the container and its drawing area (Canvas Container),
. redraw the level with the active or inactive grid,
. calculate the new OffSet,
. then open the new level by activating the new container with its GadgetList
However, in real life (and not in testing) with an interface to create, you don't constantly change levels.
We will draw the current level, then go back to the previous one and then return if needed
In the other models I could see, as for example in PureForm,
The children's gadgets are directly selectable but with the drawback that it is then more difficult to select the container or to use the scrollbar
However, I will see if I can optimize a bit the process.
For your 2nd question, to copy and paste from the list controls panel.
I note it as an idea, but I'm not sure it's really useful to do it from this list.
When you paste an object or a group of objects, there is a strong chance that you will want to move them later.
Thus it seems better to do it from the drawing area : Paste and move, paste gadgets are selected by default
But it could be feasible, to see for later.
Thanks for your feedback