This may seem silly, however I think it's a problem. If I delete a picture, and its thumbnails, from disk and then go to the album to remove it from the gallery all is well (it does it, after having first displayed just the picture title rather than a thumb). But if I delete the entire directory from disk, then go to the Album and try to delete a picture (or all pictures) I get the following error: "Directory 'albums/[Category]/[Album]/' is not writable, files can't be deleted", where [Category] and [Album] are replaced by the actual directory names.
Why does the deletion succeed if all of a picture's files are missing, but fail if the directory itself is missing? What is it trying to do differently in both circumstances? In any case, if the file isn't there for whatever reason, then it should silently (without an error) simply remove the entry from the gallery.
Note: I know that it makes more sense to just delete directly from the gallery itself. However, I came across this because I'll frequently rename files. To do this, I move the files elsewhere (so that they aren't "really" deleted), delete them from the gallery, rename the files, move them back, then batch add them in again (with the new filenames).
It would be nice if there were a "remove from gallery" option that would be like delete, except that it wouldn't touch the file system itself - rather it would just take the entry out of the database...