In v2.0.8 & probably earlier, if Auto Start is unchecked, R clicking files in Explorer & using "Send To," they don't play automatically, but work once you hit Play button. In VLC 2.1.0, w/ Playlist > "Auto Start" unchecked, files won't play at all (even hitting Play button), using Send To from Explorer.
So, that's the difference in v2.0.8 & 2.1.0. May / may not be a bug.
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The VLC preference settings are stored per use acct (I'm only using one). Thus, if you start different versions - w/o making changes to preferences, each version is using the same preference settings. VLC 2.0.8 portable still works using "Send To" for vid files from Explorer, while VLC 2.1.0 portable does not.
Since both versions are using the same preference settings file Using portable 2.1.0 in Vista x64. In previous versions (installer or portable), if I added a VLC short cut to the Windows users acct "Send To" folder, then right clicked any media file in Explorer & chose VLC to "Send To", it worked fine. Until v2.1.0.
Now, it pops up the "Open Media" UI after I use "Send To" for a file from Explorer to VLC 2.1.0, then click play button.

This never happened in any other versions. Don't know if it's a bug, change in VLC function, change in VLC default settings.
I don't want to "Add files" to any list - just R click & play & not save anything in a playlist.
Can't imagine why you'd now have to do something special in VLC for this to work. This method works for any other app, that can open the file type you're sending to it. It's still working in v2.0.8.
Thanks