You can’t “open” an RD file for editing again. It just imports the vectors, not the cut settings. RD files are in “machine ready” format, so things like images and fills are converted to just movement sequences for the machine, so it would be impossible to recover those, or anything similar.
For example, as a LightBurn file, we save text as the text you entered, where you placed it, what font you used, etc, so we can rebuild it. When you export to RD format, it’s just movements with power - all of the “source information” is lost. RD format should only be used to send to the machine, not to save and re-edit.