I don’t think so, but now I replaced RT 5.9 with RT 5.8 on my imac and processed the first rose file again and there are no differences (that I see or bother me!) between the exported JPG and RT 5.8 editor. WYSIWYG, no trial and error for exports.
Thanks for all your help and patience @Claes, I guess I’ll have to live with v5.8 for now until RT 6 sees the light of the day. 
