How to configure ART for 1366 x 768 ?

I am preparing our content to a resolution of 1366 x 768.  ART seems to recognise the resolution settings that I’ve put in place for the course material.  However, for the simulation user interface it’s a completely different story.  When the simulation is launched after a publish, the screen seems to resize to dimensions that I cannot make sense of i.e. they don’t appear to relate to the settings I’ve specified in ART.  For reasons I don't understand... following the publish I am presented with a screen that's much bigger than the resolution specified, or, I get a smaller screen with scrollbars.

alvshill_0-1583426136517.jpeg

I’ve also tried both the Resize and Center, and Do Not Resize modes.  FYI, the simulation was recorded with the screen set at resolution 1366 x 768. 

I’ve checked both the Micro Focus training courseware, and also the manuals from the Ancile website, and there isn’t much coverage or explanation of the screen sizing settings from a troubleshooting point of view, or at least not any that I’ve found.  Can anybody advise of the configuration changes and steps involved in properly configuring ART for 1366 x 768?