Spent most of today working on this.
Now the side-panel is no longer an "Everything all at once" panel, and is instead a series of tabs that you have to flick your way through.

This means I can now fill each tab with different elements and GUI bits and pieces.

Next is all the mouse/touch stuff on the main display, to let you slide and rotate and scale the elements.
... AAAAARRRRGH!!!!

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