Grammar checker serves up a new one

Microsoft's bizarrely judgmental grammar check objects to this sentence:

The embarrassed look returned to his eyes.

It has a problem with the word "embarrassed." Here's their explanation:

The marked word can be used correctly only after a noun. However, in some cases, the form of the word may be changed, leaving the word in its original place.

And they illustrate it with "the asleep child" and "the sunk boat".*

So, per Microsoft, you can't put "embarrassed" in the attributive position. "They sat in embarrassed silence," says the MacMillan dictionary. Wrong! Oxford Learner's say "Her remark was followed by an embarrassed silence." Also wrong, according to Microsoft. Wrong, too, are all the people who write things like: "how to help an embarrassed child" or "many thanks to the embarrassed man who couldn't get his kite to fly!" or "late night hosts Thursday roasted the embarrassed politician like he was going out of style" or "embarrassed dog walks away in shame"...

Seriously, I have never heard this before. Have you?

* note: all the a- forms (alone, asleep, away**, afar, afloat, alive, afraid) must be used predicatively, because they began life as phrases and English doesn't like prepositional phrases in attributive position. No the alone man, the asleep dog, the afar ranges, the afraid child ... just as no the across the river bridge or the on top of the table book. Note that you can in fact use these postpositionally: one man alone could never do it, a dog asleep should be left to sleep... Neither "embarrassed" nor "sunk" fits this category, so I'm guessing Microsoft shoehorned two rules together (and even though they say "only after a noun, I don't think they really mean to accept "the look embarrassed returned" - even though they do! Seriously, Microsoft?)

"Sunk" and "sunken" are another interesting paradigm; here the participle has split in two, one form for verbal/predicative use and one for attributive. A sunken boat, but the boat has sunk. A number of these exist - some regular where the -ed retains its status as a separate syllable (the learnéd judge as opposed to I have learned; the wingéd horse as opposed to the birds have winged their way south) but a few, like this, are irregular (a stricken look but I have struck him; wrought iron but (for most people) he had worked with metals for years).

** Yes, you can have "an away game", but that's about the extent of it. No "away home" or "away journey"...