Our team noticed recently a potential bug with the Preload Progress Dialog Box in TestStand 2014. We have a number of complex sequence files, some of which take many hours to execute, with many calls to LabVIEW 2014 modules.
For the extremely long sequence files (> 6 hours execution time), we found a problem with module preloading - under certain execution conditions (specifically when the sequence file is being called from a command line system exec via a LabVIEW application) the preload progress dialog box would begin running and permanently livelock itself, looping across a series of modules and never completing.
We've gotten around this issue for the time being by setting the Preload Progress Dialog Box Delay in Station Options > Preferences to -1, disabling the dialog box. But perhaps there is a root cause for this issue that we can address more directly?