You see how many possibilities there already are and here all monitors have same resolution, but a lot people have mixed monitors there and that makes it even more complicated.
it comes in some setup situations nonsense not to mention that the workload that comes with even serving only partly the possible situations will increase the workload up to not doable ;)
There would be a possibility to solve that problem but that becomes more a long term project, we might if pingou agrees do an GSoC project and adapt Nuancier that we have an always open submission phase for pictures that are big enough for multiple monitor setups and implement also an mechanic that you can choose you monitor setup and download the correct sizes. But that is really a lot of work, so really something for GSoC
br gnokii