I saw it at TIFF (obviously, it's the world premiere, hasn't been screened anywhere else). If it gets picked up at TIFF for release, it will most likely be by Entertainment One and Canadian distribution only. Doesn't mean you can't import and I will definitely be picking up a copy.
As for the transformations, the build up to them was more "erotic" ("fetish thing," as you say) than the actual TF, but the TFs looked fucking phenomenal. People were debating in another thread about how practical is the only way to go, but the directors spent ten minutes discussing how great practical effects are, but they can only do what physicality allows them to do. CGI and practical is necessary to give us the true TFs we want, and these guys definitely delivered. One of the directors did most of the CGI himself, aside from the "biggest TF," which was the tentacle thing. I don't know what animal it was though, sorry.
The transformations are forced and painful, but "necessary" (I will not elaborate as it constitutes a spoiler). To expand on "unwilling" might ruin the film for you. There is no skin ripping but after the snake TF she moults. And they are definitely not "smooth."
For the first half, before the mystery is "solved," the transformations are mysterious, terrifying, and erotic. After it is solved, they are more humourous, and maybe a little erotic. The first few "TFs" are undetermined animals because we don't see how far she gets. It's implied that it is a different animal each time. There is also some offscreen stuff, but they don't use it as an excuse to cheap out. There is always a story-related reason for everything they choose to hide.
If you want more details, you'll have to ask specific questions. I am happy to oblige, but I need to know what you want to know.
EDIT: Just remembered something. Her TFs begin with her skin doing this kind of "rotting" or "crawling" thing. Sometimes she manages to stop them before they happen, and sometimes she can't. She has some kind of injected medicine to help hold off the TF, but think of it like the "cure" in "Ginger Snaps: Unleashed." It only abates the effects for a certain time before something has to give. But unlike Brigitte, she transforms back (seemingly in the morning). Oh, and she eats live animals when transformed and when transforming. I think she tries to prevent a transformation by eating a pet rabbit (almost like zombie-Sally in Being Human Syfy), but she is unsuccessful.
Also, I personally think this will go down in the fandom as this decade's "American Werewolf in London" or this decade's "The Howling" or this decade's "Ginger Snaps." It may be too early to tell but the TFs were detailed as hell when we saw them, even if we didn't see everything.