I suggest that the timing edit page (timing for hightlighting each word) should have a relative/absolute mode button. If it is absolute (default), just change the single timing element. If it is relative, then adjust all elements after by this word by the same amount as well. I have come across an example where I pause too long on one word and all of the words after then play too late and I would have to edit each word thereafter manually even though the timing is well done, just not in sync on one word early on.
Customer support service by UserEcho