I think you have mis-scored many of those clips. For example:
According to the poet, April is the cruellest month
- TS Eliot being called out for an alleged spelling error. Whatever next?
Cathy took two hundred and ten pounds out of her bank account,
- Common British idiom, and the comma at the end doesn’t matter.
His central heating had stopped working,
- Common British idiom, and the comma at the end doesn’t matter.
The correct pronunciation is.
- Seems a valid clip. Not a full sentence admittedly, but quite readable.
The drawer drew a lifelike image of the man.
- “Drawer: a person or thing that draws” (Collins Dict). Nothing wrong with this at all.
By my count, you’ve mis-validated half the examples you gave. I also find it rather worrying that you give “One way to annoy Gill is to spell her name Jill” as being “an edge case outside the rules.” No it’s not: it a perfectly straightforward English sentence that 100% of British English speakers would read correctly without hesitation. It brings in two very common spelling of the same name, and of course we hope will be read properly, not guessed at by readers who may never have seen one of the spellings. If I see a US word I don’t know how to pronounce, I skip it: isn’t that what the skip button is for? May I suggest you bear in mind when reviewing sentences, too, that not all versions of English use the same orthography and grammar as you do? We are building a corpus of many different varieties of English (of which US and UK are only two examples).
Michael