Another temporary solution is to use GMIC-qt as a standalone application. Just run gmic_qt (in Linux, don’t know about Windows) and it will ask for an image file to open. The rest is the same as when it’s executed as the plugin, except for that it will show the resulting image with an option to save it (don’t forget to add the file extension, otherwise the file won’t be saved - that’s sort of a bug, I added the issue to the GitHub).