I often export my Geometry to Rhino 5, since this is what my business-partners/suppliers can open. When I export, it NEVER does comes up with prompt window the first time, where you can click/select Rhino 5 / Rhino 6-export. Even though the file is saved, the file/export fails to open in Rhino 5, which means it saves in Rhino 7 format. It’s ONLY after the second time when you perform the export, that the prompt window appears, and the export is correcrtly made. This is an old bug that exits in Rhino 6 also.