There's still many things that need to be done with the video support so it's currently incomplete in it's replacement. What you've noted is on my existing todo list, I just haven't focused much on video as for most it's not a priority.
With the classic skin playlist buttons (as that's the only thing I can think off to match what's being described), the option you've noted doesn't relate to that. I made a decision early on when I replaced the playlist editor handling to not re-implement the skinned menus & instead go for something that's more consistent with modern skins whilst improving accessibility.
However I only see those actions working similar to the manner described when doing a double-click in a plain 5.666 due to how the menu first triggers to display & then you're hitting the same area & that registers as an action. I'd be fine with adding a shift+click action or trying to support double-click to try to get close to the winamp behaviour.
-dro