I thought others discussed visual mark-up programs before for use in classroom or presentation, but I couldn't find them.
In any event, I saw this link to VirtualBoard, a free program that allows you to do screen mark-up while running BibleWorks or other programs. Seemed like it might be something helpful for others, based on this video by a well-known BW guy.
The link I saw made it sound like it was a "new" thing that this program is now free (i.e. it used to cost money). So check it out.