At this point, this project is nearing feature-complete'ness, and is lookin pretty good. This could be considered a first release, although there is no such thing. A lot of significant updates have gone in recently, that I wanted to mention.
8/13/2017; Preferences panel - Added a preferences dialog to allow users to configure different bits of player/playlist/view functionality.
8/11/2017: M3U playlist support - Added support for M3U/M3U8 playlists. Also, app now allows and properly resolves file aliases and symbolic links.
8/10/2017: New HTML User Guide - Completely rewrote the User Guide. It is now in HTML format and explains all features in detail, with lots of screenshots. Did away with the old RTFD format User Guide.
8/8/2017: Demo videos - Added lots of .mp4 demo videos that illustrate different features.
7/28/2017: UI overhaul - Major overhaul of the UI. New color scheme (dark background, light text), new slider control look and feel. Each slider control has an accompanying label showing its value, for instant feedback when making adjustments.