Finally learned how to do this today! I thank Nick in support for this (though it took me a while to recognize a little idiosyncracy of the process that he did not emphasize).
To erase words in ?block?:
1.Put schedule in ?all providers? view
2.Click in the BOX where the words to be deleted are; the row will turn blue
3.Select the time to be blocked by clicking to the left of the time slot. The row will turn green.
4. Hit the delete key.
Oddly, you must do it in this sequence (turn blue, then green) or else it will not delete.
