This issue was first noted in 0.9.16, and renaming the LBFileDialog.exe seemed to resolve it entirely. I recently started having crashes again, and noticed that this file had been restored, presumably with a 0.9.20 upgrade.
The symptom is intermittent system hangs, generally when doing some form of file operation with the dialog open. This flows on to hanging the main Lightburn executable, along with usually some form of Windows explorer hang as well. It can be resolved by terminating the process for LBFileDialog, Lightburn and explorer.exe, but at the expense (obviously) of losing any work in Lighburn that is unsaved.
Renaming LBFileDialog.exe out of the way seems to make the problem go away. This in on a Win 10 x64 system, running 0.9.20.