FYI - it appeared that something had recently changed that was limiting the functionality of the SMART Mobile desktop simulator. It would not open correctly and, when I ran as an administor, it would open, but it wouldn’t pull mobile packages in from the desktop.
@justinsteventon flagged that more recent builds remember where your window is, so it could be that it was attempting to put SMART Mobile on another monitor (or a projector I had used in the past).
I was able to reset this by deleting Desktop\CTProjects\Settings.ini and then restarting the SMART Mobile Simulator. All is working as expected now.