well I've resolved it now, but it's the kind of thing that will trip people up. They will expect OPENLANE_IMAGE_LANE to give reproducable results

Well… it’s a weird situation. In a vacuum, I’d prefer to keep IMAGE_NAME unprefixed for the OpenLane Makefiles. But I also understand that the majority of the userbase is probably using OpenLane with the Caravel User Project, where they’d expect OPENLANE_IMAGE_NAME to work with the OpenLane Makefile. I’ll open a strawman PR and put it up for discussion.