I don't know when it started but since a couple of weeks I noitced the my Export Log are unusable.
The issue is that the order of actions in the exported log as HTML page is completely wrong. It looks like it starts with something from the middle and finishes with something from the start.
Can you please try with the latest test build of FB4 please, I seem to have a vague recollection of this issue but not sure if this build fixed it or not.