Hi ,
I ran in to the same issue and I think I found a workaround. It appears that the Etcher program does not like my SD card reader. The work around was that I turned on Etcher without the SD card reader attached and then I selected my disk image file (.img), next after selecting the image I get to the disk part of the wizard and of course it cannot find my disk, so hit “continue”, now plug in the SD card reader with the SD card and it should auto detect the card and select it for you.