I have been asked by a provider to make a small change in her review.  I have no problem doing this, I just misunderstood one of her likes/dislikes.  It would not affect her standing or her score.
But I can't figure out how to do it.  Any help?

Like a small change of a menu item. If it's more complicated, use the "contact us" button.

though I could save time by cutting and pasting, then making the edit.

As long as you are in the 90 day window to review her, it is fine.

The new review replaces the old one.

I was allowed to edit a review just by telling them I needed to edit it. They opened an edit window. I did what I needed and resubmitted.

In the OP's case, it sounds like he just needs to change something on the profile (I could be wrong, but that's how I read it).
If that's the csse a problem report should do. If more than that, then a "contact us" should do.