Thanks a lot pdurrant for the little app! It works beautifully!
Now, just out of curiosity (and because I'm interested in learning the nuts and bolts of the epub creation process), if I were to do in Terminal what your app does for me, which commands wound I have to enter? The ones in the first post of this thread don't seem to work. Sorry, I'm a UNIX noob. I keep getting messages such as "name not matched: mimetype" or "zip error: Nothing to do!"