Right, I just read all the last few posts "properly" now my nephews have finally gone, spotted the perfectly reasonable suggestion of editing covers for books with no formats and upped the new zip (again). My apologies to the couple of you who downloaded in the meantime and many thanks for calling me out on the bug I left in it.
My last minute epiphany today of one last feature (disabling the menus where cover/formats not available) clearly bit me, should know better by now. I didn't count on the constant need for attention of my 5/8yr old visiting nephews every 2 minutes and did half a job on it.