Not a Valid Lectora Zipped Title

The file fairies have raided my powered-down computer and corrupted a large course. All I have remaining is the contents of the course that were unzipped by my LMS. Trouble is, when I try to re-zip and then import into Lectora in order to make changes, I get some ignorant error saying that the "file is not a valid Lectora zipped title." Anyone know how to convince Lectora that the files are valid? I tried threats and curses, but nothing is working.The file fairies have raided my powered-down computer and corrupted a large course. All I have remaining is the contents of the course that were unzipped by my LMS. Trouble is, when I try to re-zip and then import into Lectora in order to make changes, I get some ignorant error saying that the "file is not a valid Lectora zipped title." Anyone know how to convince Lectora that the files are valid? I tried threats and curses, but nothing is working.