UPDATE -- this same behavior (attempting to interact with ANY LabVIEW window at all, yields only a beep (the Windows "Default Beep" sound) when clicked upon) can also be produced from a completely different scenario. These same symptoms are also occurring as LuaVIEW VIs are dropped onto a block diagram; either by dropping them from the LuaVIEW palette, or by drag-n-drop from Windows Explorer. This is confirmed on two different machines running LabVIEW 2011/SP1 (v11.0.1f1), and on one machine using LabVIEW 2012/SP1 (all 32-bit LV on Windows 7/SP1, 64-bit).
As usual, thank you for the help. I look forward to the next beta release, and eventually final release.