So, I am only assuming that the Blur plugin works correctly in CV as I do not have an executable that works.  Since the HV version (8 and "latest after 8 binary" running on Ubuntu 18) appears to be the same flaw as CinGG, it must be that the CV experts fixed it at some time.

CinGG was based on HV initially and then the CV mods were merged in but when there were major differences between .C programs/.h headers, a decision had to be made of which to use.  Apparently in the case of Blur, the wrong one was made based on the assumption that HV blur worked in a quick simple case of a single track video.  What a disappointment that patches and improvements are not accepted and merged into a base.

 

Anyway, I will see if I can fix CinGG blur based on CV code which varies greatly from the HV code.  Hopefully, that will be easier than Chromakey where I have made no progress.