All the ummm.ummms...etc are very distracting but it seems like she uses this as a stall tactic in order to clarify her thoughts. Pretty high pressure situation for this lawyer and hopefully after the trial this can be worked on.
Don't know that I would do any better - but it is distracting and annoying.
Silence is golden. Doesn't show up on transcripts, and it makes the witness nervous. She should use it more often!
My Dad, a very wise man, once told me, "if you don't know what you're going to say, shut your mouth, or else the umms and errs are going to make you look stupid, and you don't want that."