After a good bit of tinkering, it seems that I have come to resolution of my issue. For reasons that I do not completely understand, it appears as though the installation of PinballX did something to my system such that it relocated the content of the DMD window to a location on the screen that was not viewable in my setup. This only appears to have happened to these two games initially. The solution that I ultimately arrived at was to change the resolution of my DMD monitor from the default of 1024 x 768 to a resolution of 1280 x 1024. After the resolution change, I could see a tiny portion of the DMD content in the lower right corner of the screen. I spent the next bit of time adjusting the X,Y, Width, and Height settings in PinballX to get the content of the DMD mostly properly viewable within the window. It's not a perfect fit but, it is at least viewable which is a wholesale change from where I was before. The really odd thing about all of this is that, before I changed the resolution for the DMD monitor, all of the games were displaying their DMD content properly with the exception of Scarred Stiff and Big Bang Bar. After the resolution change, I was able to observe that all of my games DMD content had shifted away from where it was previously displayed.Additional oddity was that, in Visual Pinball I would observe the same behavior with all games except these two, working properly. I was under the impression that the PinballX setup would not alter my Visual Pinball settings. Maybe that was a bad impression? I'm not really satisfied that this issue is not completely understood by me. I'd really like to have a clear understanding of exactly what happened as well as the solution but, I guess I'll just have to settle for the solution to my particular situation at this point.