I realize the panels are unitless, so the dimensions aren't "real". But, there are the issues of how coordinates are stored, so JMRI probably has some grid and panel size limits. Likely limits are powers of two; 1,024 or 2,048,..., 65,536, and so on. I expect them to be no more than 16 bits for X and 16 more for Y values. Perhaps they are the same for all panels, perhaps not.
How big can panels be, and how large are a few realistic examples for Layout Editor and Control Panel Editor?
My LE panel is 780 wide by 410 high, and probably will need to be about four times that area, whether doubled in each dimension or converted into four sections stacked one above the other. Will that be too big? Could it be extended to about 4,000 grid units wide or tall?
One reason it's using so much space is that my parallel tracks seem to need to 20 grid units apart to not snap together where I don't want them to do so. Perhaps there is a way that can be changed.
Don Weigt