W10 x64
Just installed, First file I opened:

The Book Browser was SORTED by name with no user input
Titlepage and Jacket are now at the END. Thankfully, the other sections were simple-sequential and stayed in order.
BTW I think this (unwanted sorting) was what happened to me with 901, but in that case, the files had various
Names and I had
fun 
putting things back to rights
BTW I have now removed the tick for gumbo tidy on open and will see if that helps