there is no update beyond what is here for book designer
https://www.mobileread.com/forums/showthread.php?t=11786
I dont know how much you are editing books, but using BD ussually takes all of 5 minutes to mark all the chapters, and Make a TOC, and then give me a very nice LRF that is not slow at all. though i load books using Sonys Software.
check out this thread about my testing with fonts
https://www.mobileread.com/forums/sho...4&postcount=19
https://wiki.mobileread.com/wiki/Book...505.2C_and_700