Okay, back again.
I'm able to delete selected annotations from the "pen" or "marker" as long as the annotation is not a straight line. If I draw, say an imaginary wall, on the map using the pen and make a straight line, which I plan to delete once the party discovers it, I find that I can not select the straight line. If I put a little bend in the line, it allows me to select it for deletion. Any ideas what I might be doing wrong?