More info from B. above.
I set up a 5 movie conversion (using Video Converter). These movies were feature length 1080P and 2 to 6 GB each. No changes were made to any video/audio/subtitles settings. This was just a straight simple conversion. First one finished fine. Second one showed as processing on “Processing” window, but file name in output folder was one of other movies. Third, fourth and fifth conversions were even weirder. “Processing” window indicated everything was finished (nothing in progress), but remaining files eventually showed up giving me the illusion that things were still happening in the background. I repeated the test several times changing the order of processing of the 5 movies. Each test started with an empty output folder. Each test resulted in nearly the same outcome. Note that there was no black CMD window anywhere. I suspect that there is something impacting the queue handling or maybe the status refreshing on the “Processing” window is broken.