Hi @tom9,
I stumbled on this unanswered question while doing a community cleanup.
As far as I know, the only way to do highlight annotations in Docviewer (the part of SpeedGrader where a word/pdf/etc submission is shown), is through clicking and dragging with the mouse. I wish I had better news for you, but wanted to at least provide this info now.
We are marking this post as a solution to help Community Members find and respond to the newest and most active threads.
At any time, any Community member can click the “Not the Solution” option and then respond in-thread with your follow-up questions. It’s important to include @CommunityForums in that reply so we can restore the entire topic to our list of unanswered questions we check routinely.