Theresa,
As mike said, changing titles does cause problems, but only temporarily. That is because the title of the image is used to construct the web address of the work. A title change breaks the link until the FAA database is updated, which I think is still once every 24 hours.
I am not changing titles, descriptions, or anything other than uploading a new file to overwrite the old. Still, I thought I had read where people had problems doing that.