Did any of Alfred Hitchcock's American films receive poor reviews upon release?

Psycho opened to very mixed reviews. A summary of a few are found on it's wikipedia page.

The bad reviews called it a blot on Hitchcock's career, a gimmick movie, and that it looked like a TV show padded out to two hours. One of my film professors hated it, saying that "you shouldn't need to explain the ending of your movie in your movie."

The New York Times on The Trouble with Harry:

"It is not a particularly witty or clever script that John Michael Hayes has put together from a novel by Jack Trevor Story, nor does Mr. Hitchcock's direction make it spin. The pace is leisurely, almost sluggish, and the humor frequently is strained."

Hitchcock likely received bad reviews as commonly as any filmmaker did in his day or ours. Criticism is by definition made in the eye of the beholder: a subjective review.

The thrust of your question appears to be more about "how did viewers react to socially shocking elements" in Hitch's films. That question, I would suggest, is self-answering. Hitchcock wasn't afraid to tug on cultural norms a little bit in order to influence his audience, to make them uncomfortable. The plot itself of Rope (1948) is arguably an exercise in this tactic.

Worth noting that when you reference "Hitchcock's American films", that period is generally considered to be from Rebecca (1940) to Family Plot (1976), well over half of his career. Of those, very likely the worst reviewed of the bunch, albeit something of an outlier, was the domestic comedy Mr. & Mrs. Smith (1941). He never dabbled in straight comedy again.

Regarding Psycho and the references Legion6000 gives in his answer, keep in mind that Hitchcock produced the movie with his television crew. He did this in order to produce the movie cheaply under his own expense since Paramount didn't want to produce the script. I also recall that he wasn't happy with the tacked-on ending of the psychologist's explanation, but I don't have a reference for why. Possible that's from Francois Truffaut's interviews, which I highly recommend reading if you're at all interested in Hitchcock's work.

I had the impression for years that his last movie Family Plot was widely panned, but cannot substantiate it right now. All the reviews I currently see use mild terms like "witty relaxed lark" (Canby), "not exactly top-tier" (Anderson), mixed in with others that list it as a "complicated delight" (Ebert). So, is this fawning, lackadaisical praise for a director past his prime? I really can't tell if they're using terminology to say it's bad, or not-that-good.

If you visit the review pages in IMDB for this film though, the public at large have no such trouble deriding it.

The 1944 film Lifeboat received critical reviews.

2 reviews from New York Times columns, quoted from Wikipedia:

[Bosley] Crowther wrote that "the Nazis, with some cutting here and there, could turn Lifeboat into a whiplash against the 'decadent democracies.' And it is questionable whether such a picture, with such a theme, is judicious at this time."

and

In Truffaut's 1967 book-length interview Hitchcock/Truffaut, Hitchcock paraphrased Thompson's criticism as "Dorothy Thompson gave the film three days to get out of town."