In my eyes the size of a room is not limited. You should not use sprites or background images greater than the resolution (approximately). But you can build a huge room based on tiled background images for example...Sure, tiling is an option but you still need to add a background image (transparent png or webp) with a canvas size of what you want the final size to be as the background image is what the scene engine uses to determine the scene size. Even a blank transparent background image will be eating into your VRAM & the larger the scene, the more VRAM that is going to be required either way - meaning owners of potato pc will probably have an horrible experience with trying to load/run your game whereas proud pc master race owners of super powered potato machines will probably be able to run your game at a gazillion-billion... FPS without any loading times. It's all about the optimization & 1080p+ is heavy on system resources.
In my maze game I use a background-picture of 2500 x 2500 px. There is only one scene to walk throught (like your idea of the house) up and down, left and right. I tried 3000 x 3000, but it doesn't work - the picture wasn't seen in the game. So I think you can't use unlimited sizes in Visionaire. Maybe it depends on the PC you use (better PC allows 3000 x 3000 or more), but it make sense you use a size which you can see in the editor and in the player. Think of the possible restricted hardware a player will have later...I believe it's the y-axis the editor/player seems to have an issue with. If you keep the height about double or less of the default resolution (1080p) then it should be ok. I think for width you can maybe go up to 2x or 3x 1920x1080, but not 100% sure. Still my point remains, for 2D 1080p games this wouldn't be ideal anyway, unless you are procedurally loading & unloading content as you move across the screen - otherwise you would have stuff off the scene doing stuff even though you can't see it which would be a pointless waste of system resources.
I believe it's the y-axis the editor/player seems to have an issue with. If you keep the height about double or less of the default resolution (1080p) then it should be ok. I think for width you can maybe go up to 2x or 3x 1920x1080, but not 100% sure. Still my point remains, for 2D 1080p games this wouldn't be ideal anyway, unless you are procedurally loading & unloading content as you move across the screen - otherwise you would have stuff off the scene doing stuff even though you can't see it which would be a pointless waste of system resources.I used a scene picture of 3200 px width and 768 px high to scroll with the walking character, it works. I don't know if I have to use fixed values (1024, 2048 and so on), because the picture is bigger than the game resolution, so I didn't care.