Greetings, I ran into a problem when I was using the custom-ov approach with the union option. It seems my version of busybox mount doesn't like it when there are two directory separators in a row. So I added a small sed step to clean any duplicate separators that might be present. I also found that when using the union approach that it did not get the correct rofs_dest_backing because the loop to configure those only was enabled for links. I have attached a patch that addresses these two issues. Thanks!