please, give me an advice. I want to set a custom background (PNG image) for each diagram. Ideally, the background should be saved with the diagram. I need to draw a diagram of a computer network and active elements in the floor plans of buildings. I can't set it up so that the background is saved together with the diagram (png image). I still have one background, although I will open another diagram, which should have a different background. please advise how to do it so that I have 4 floors of a building, 4 different backgrounds and a different diagram for each. Simply described. I will open the 1st floor and the 1st floor giagram will open for me, including the background of the 1st floor. other files will be 2nd floor, 3rd floor and 4th floor. thank you