Undo (Ctrl-z) Function

[dvhirst]

So, I am working my way through learning to effectively use the Line, Arrow, and Text tool, after downloading and installing the most recent release (8.0.127). My question: why doesn't the Undo function work and undo the last action I took? I tap Ctrl-z while in the tool and exactly nothing happens. It would be very useful and would help me down my learning curve if I could undo the last step I took (which didn't do what I expected it to do). Thanks.