*sigh* This game simply went downhill quite quickly, that's what happens when you want to tackle so many things at the same time, specially since creating eroge games is not your main line of work / income, and you have little time available to pour into developing said games
The Devs have stated that mangomango is currently suffering from "burnt out syndrome" (over stressed and over worked on their own words), and that they are trying to hire extra programmers to ironing out bugs on the game, and anyone else would say is a good thing, however, unless you hire a full time programmer team, all the coding will end as a "spaguetti code" because every programmer have different ways to tackle the coding, and if there's no standarized guidelines for the programming, all will be a mess in quite short term
Furthermore, they switched to Unity a couple of releases ago, and that change brought more issues than they expected, and they still linger on the game, which causes delays, as expected, and the artwork has going down in quality as well, as you can see, this is just issues over issues on top of more issues
What I would do, is take an administrative desicion, to freeze the active development of a couple of projects, and put those on the backburner, notify to the public that those projects will enter a hiatus, or will have their development slowed down, to focus on more important projects, or projects that have more traction with the public (data analytics is your friend), and try to finish said projects, or at least try to fix as much as possible on issues cropping up on those projects, so the development will be easier in the future