Hi,
thanks for your suggestion. Indeed it’s not currently possible to copy and paste non-text. At the moment, what you can do is either use drag and drop (drag from any folder whichever side will drop the file on the desktop), or the file transfer tool from the NoMachine icon in the system tray. The downside, as you wrote, is you have to have the image physically on the system to be able to transfer it and then you have to remove it by hand. Good news is that we are re-evaluating adding support for copy/paste of content such as images, with the possibility of adding it in an upcoming version. Current development priorities mean that it’s not something for an imminent version, but we’ve taken note of your request 😉