The NewExpression button doesn't do what it should.
It seems to cycle thru history - changing the TestCase area to previous blocks of text I've had in there.
While a proper history would be great (even, F7/F8), NewExpression isn't the place for it!
Also, the screen shot for this window in Help is out of date (as are, I suspect a lot of screen shots now given the new icons).
In this case though help is way out of date - still shows Brief and Unix Regex options.