Still not 100% sure where your at in the story but it sounds like you should be around "talking to mark about perfume", but you said you talked to everyone. So, maybe "find vera"..
Here is a screenshot of my task list just after the last quests you said you had and the second screen is pointing at some rocks where Vera will be when you find her behind the building..just incase because I didnt know what building it meant and didnt see her for awhile.
When I was done with Nana, I met Vera and I have talked to her some times, also done wine tasting and cooking for her, but there is no progression. Vera is walking around from house to house, sitting outside on a chair etc.
At this time, after having sat down with Nana and had the kiss, it is evening (in savefile it says 2200h) and girls plus Mark just wander about a bit.
Vera says that she's kinda sorry about her way of acting and commends the MC that he is doing so much for them.
So the thing is, progression is halted for some reason. Not knowing if the problem is Nana with the closed curtains. I can cook for her, but of course, there is no way of interacting with her then, and afterwards she's just gone again.
I found my latest autosave which was from before Nana closed curtains and think I will try that day over. I'm just surprised they would release a game which can lock up completely with no means of remedy.
Thanks.