The crash is occurring in a third-party DLL called axTotalConverter64.dll which seems to be part of "TotalPDFConverter", "TotalImageConverter" and "TotalMailConverter".
There could be several ways to fix it (including uninstalling those programs) but the best way depends on what's triggering the crash. Does it happen when you right-click on files? Or when reading folders? Or... ?
I have identified that the offending dll does indeed belong to Syncfusions TotalImage Converter and I have uninstalled it and will perform tests to see whether that has resolved the problem.
Incidentally, the instant I uninstalled the program I received an email from Syncfusion asking why I uninstalled their software. I have informed them of the issue and they too will examine the problem.
I have now conducted further investigations and established that:-
The offending dll (axTotalConverter64.dll ) was actually installed in Program Files (x86) - the 32 bit Windows Folder
When Total Image Converter is installed it inserts axTotalConverter.dll and axTotalConverter64.dll in the 32 bit Program Files folder. This must be an install error!
I removed axTotalConverter64.dll from the 32 bit Program Files folder and am delighted to report that since then both Total Image Converter and Directory Opus work flawlessly.