Can't View Vdh File While Downloading Anymore

I used to be able to watch a video/movie while downloading, but ever since I reinstalled VDH (on a new computer), it won't let me view the video until after the download is complete. My connection is not that fast, and I would prefer to see if the video is interesting (and stop the download otherwise) without waiting 30-60 minutes for the download to finish first. I have vdh 6.1.1 installed (as an addon for Firefox 50) on a new windows 10 computer. I'm not sure what vdh version I had on my last computer (it is no longer with us) but it was a windows 7 computer if that helps/matters (also using Firefox). Is there something that needs to be "checked", or "unchecked", or is this normal behavior for vdh 6.1.1. I like to keep my apps current if possible, but if I have to revert to an older version I will. Thanks in advance for any help/ideas.

 

Thanks for the redirect, plodr. VLC is now working as it used to.