If you edit a photo in an external editor and you don't want to hide the original unedited photo to be hidden after returning to Album, use the Save As command in the external editor to Save the file under a new name. When you return to Album, you will be prompted with the choice of only showing the new version in the photo well, or importing the edited version as a new file. When you choose the second option your original photo will still be visible in the photo well, however, the edited version is treated as a completely new file, which means the tags are not carried over.
If you want to keep the original visible, and retain the tags in the new version, try to remember to duplicate the original before launching your external editor. When you are finished, you can use Album's "Replace Original with Edited" command to conserve disk space. (Otherwise you will have two originals stored on disk--the true original and the duplicate.)
