Upgrading to Powerpoint 2013 appears to have resolved this issue. I can now advance to the next slide using the Keyboard shortcut or the "Move to next" button.
However, now I have a different issue.
When I have a presentation showing, and then select the "show black" option, when I send a new presentation to Live, the projector remains black.
I have the "Unblank display when sending items to Live" Option Selected, and I see the selected icon change from "show black" to "Show presentation", but the screen remains black. I can even cycle through all of the "Show Desktop", "Show Black", and "Show presentation" options, but the screen remains black. "Show Desktop" does Not show the desktop. "Show presentation" does Not show the presentation.
However; If I move to the next slide it will then begin displaying, but then I have to quickly switch back to the first slide. This is confusing for my volunteers, and distracting for the congregation.
I also noticed that if I move my mouse over to the Projector screen, I get the PowerPoint options at the bottom of the screen. If I select the Three Dot option button, then select "Screen", I can select "Unblack Screen", and that will cause the presentation to show.
It seems OpenLP is Enabling the "Black Screen" option in Powerpoint, but then does not Disable that option until I advance to a new slide.
Since I've seen a drastic change in behavior in OpenLP after switching from Powerpoint 2010 to Powerpoint 2013, I am wondering what versions of Powerpoint you used in your testing and development? Is there a Recommended version of Powerpoint?