It was a rough ride, but I made it through chapter 4! The game now has even more puzzles and areas in just one chapter, which keeps the game flow going pretty well, if anything I'd personally prefer the puzzles being tied to the plot or the mc a bit more at the first half of the chapter (like how the moths speak to Oliver), and that the new areas are explorable (therapist room).
I downloaded the 2.0.0 version when it came out, so the response options at the beginning of chapter 4 kinda bugged, I chose the first option but it played the dialogues for the 2nd option instead, it's fixed in 2.0.1 I suppose. There maybe misplaced sprites in the therapist cutscene, as it displays Ego's sprites instead of Oliver's, tho it can be a metaphor or sth, but I haven't checked that in v2.0.1 so if it's already fixed then that's great.
And well it seems that some random winds howling for background noise is copyrighted (at 13:08), but welp yt has an option to remove it so it's fine, only drawback is that audio in the part will sound like old low quality ipods.
Spoilers:
I can't help but noticing there are several references/inspirations to TCOAAL (like how the portal and flower puzzles play out), there're also some ref to Better Half as well? Cuz you know Oliver talks to himself, Ego making suicidal/selfcest jokes, and even the line "A man who's spent the better half of a decade training to become a detective...", like there's just no dialogue out there like that lol. But whether those are references or not, it's still funny anyway, unlike the rest of the chapter...
I swear I sensed something ain't right minutes before THAT scene, and tho 6 months ago I kinda figured it out that something ain't right with the mother, I wouldn't expect her to be such a freak (literally), THAT scene really made me uncomfortable, combining with what happened in the therapist room, it's thoughtful that you implied how SA can happen to anyone and it should not be considered as "lucky" or anything positive, you did a great job with that and I think that would be the darkest part in the game (unless you make it worse in the endings somehow).
Looking forward to the final chapters! Also thanks for publishing Aquatic Grave's OST!