VIRB Edit Versions - current one is crashing

I have had VIRB Edit 5.3 installed and working for a number of years.

Recorded first videos of the year and went to edit with the linked 2 camera edit.

With 5.3 installed it gets shut down with the instruction that there is a later  version available.

When I download the current 5.4.3 and attempt to create a video, after bringing the raw files into the editor - IT CRASHES.