If the Vuo editor crashes, any already-running compositions continue to run. (You can quit them from the Dock, or if they don't appear in the Dock, you can quit them using Activity Monitor.)
This feature request proposes that, the next time you launch the Vuo editor, it would detect and offer to stop any compositions that are still running after a previous crash — more convenient than having to find them in Activity Monitor.
When a composition is an Image Generator protocol, there seems to be no way to size the output window other than manually with a mouse cursor.
I was attempting to render a composition to a 1280x720 movie file, and was noticing that after I converted it to the Image generator protocol, that I couldn't figure out a way to adjust the composition window to exactly the same resolution.
Am I overlooking some place where this can be set by inputting the desired pixel resolution for the output window?