Problem with compositor

I’ve run into a bit of a problem with the compositor. I have 3 scenes in my file, two for the geometry, and one for the compositor with no geometry. The two scenes with the geometry don’t have a compositor set to use nodes, but the third scene does.

In the compositor scene there are render layers nodes for the other two scenes, and they both save their passes into a file output node. If I press f12 to render whilst in the compositor scene, then the files output nodes work, and the exr file for each scene is saved to a seperate multilayer exr.

The problem is, if I need to re-render one scene only, then there doesnt appear to be any way to get the file output node to resave the exr, because pressing the render active scene on the render layers node doesnt appear to retrigger the file output node that is connected to it.

If I enable the use nodes in the compositor of the two geometry scenes, and move the render layers node and file output to that scene, then the file ouput node is still not triggered when pressing f12 in the compositor scene, because apparently the compositor of other scene arent used when pressing f12 from another scene.

The only workaround i’ve found so far is to temporarily move the render layers and file output nodes to the scene I want to re-render, go to that scene, press f12 to render just that scene, then delete the nodes and turn off the compositor again for that scene, otherwise it seems to break the blend file. I was unable to even open a scene if I left those nodes/compositors active.

Any chance of a dev either giving the file output node a save button so I can manually save the file, or changing the behaviour so that the render active scene button also triggers upstream file output nodes?