Hello, yes, this is a known issue. There is a workaround though, but it will need temp space on your internal disk.
First put the data on your internal disk, add the folder to espionage, let it encrypt, and once the folder is present in Espionage, click onto small "i" near the folder name to get to the folder options. There you will see a disk image drop down menu with the option to change disk image location, select your external drive and Espionage will move to the external image.
After that you will have the disk image containing the data on the external drive and lock and unlock as well as adding or removing files will work just fine. It is just the encryption processes which does not work.
I hope this helps
Cheers
Zsolt
First put the data on your internal disk, add the folder to espionage, let it encrypt, and once the folder is present in Espionage, click onto small "i" near the folder name to get to the folder options. There you will see a disk image drop down menu with the option to change disk image location, select your external drive and Espionage will move to the external image.
After that you will have the disk image containing the data on the external drive and lock and unlock as well as adding or removing files will work just fine. It is just the encryption processes which does not work.
I hope this helps
Cheers
Zsolt