Green dots mean you either: Haven't had sex with everyone yet, haven't gotten all the blessings in an area yet, or haven't beaten all the quests in an area yet.
Exceptions include: Mistral Village, which requires you to beat Alice in the Training Arena, Elysian Colosseum which requires you to beat every match, and Little Shroom City which requires you to obtain the Champion's Belt from the Battle Shroom.
Beating an area 100% can be tricky. For example, to get Emilia's blessing you need to sleep with her a second time unprompted. To get Guinevere/Automatron's blessing you need to repeat their scene and change your choice.
The best way I can imagine a sex scene with Eden or Michaela would be if they decided to betray Eris themselves and try to use the main character's power for themselves. The problem is, the main villains are all good friends and loyal, so that'd never happen.
The game hasn't been updated yet, but I'm aware of the issue and it'll be fixed in the next update, probably Episode 13.
The "NW.js" error isn't causing your game to open as a white, blank screen. When troubleshooting, I'd recommend forgetting that, and just googling something like "RPGMaker White Screen on startup", it sounds like a rendering error.