I’ve been reading and enjoying your newest story and don’t find any problem with your use of terms. The thing is the US is a large country and many terms used in one area have a different meaning or a different word or phrase is used in another.
Soft drinks are a great example in the US. Older people may order one as a “soda pop.” Some areas you order a “soda” while in others you order a “pop” and in one that I remember you order a “coke”. (I was actually asked what kind after I ordered the ‘coke’ as I quickly discovered in that area of the country coke is used as a generic term for any soft drink)

While I’ve heard many of the British word used in their correct British context, (since I do read a lot of the stories here,) Only a very few have I ever heard that are widely used in the US. And these are mostly used by people that have lived or visited other countries. Others such as ‘fortnight’ I had heard used but only found the meaning after reading stories here on BC. The word still confuses me as to its origin, as what does a fort and a night have to do with a 14 day period of time?
Autumn – It’s a season, It’s always been called that and we know that’s the correct term for the season, we just do not use it that often.
In the US when something is bloody, there is always blood involved. Americans do not use terms like “Bloody well!”
Bum – in the US this is normally used to refer to a lazy person without a job.
Cheers – It’s a drinking toast, Never seen it used for anything else.
Fancy – something elaborate, highly decorated.
Flat – having a flat in the US is not a good thing as it means you either have to pull over to the side of the road and change the flat (tire)
Frock – something a minister wears
Gobsmacked – Yes this one I’ve actually heard used although very rarely.
Holiday – President’s day, the 4th of July, Christmas, etc. specific dates that most places are closed. Taking a break for work to travel, etc. is a vacation.
Kit – a set of items created for a specific purpose such as a first aide ‘kit’
Loo – only used in the US if Spell Lou and that is short for Louis or Louise.
Queue – ding, ding, we have a winner! Yes this has become popular due to its use in computer terminology.
Roundabout – used in the US but instead describes a convoluted route or person who cannot get to the point of the subject they are trying to discuss.
Shag – Not used often but you may thank the popularity of Austin Powers for this one.
Twit – I commonly use this one personally for people that use twitter. The definition is the same 
The American terms are fairly correct, although “Two-time” has always referred to a man or woman that was cheating on their significant other. “He was two-timing her with her best friend!”
Transportation – Hate to say this but British have this one wrong. Transport is what you do, transportation is what you do it in. “We can use my old Ford pick-up truck for transportation to the Cubs game. We can transport the cooler full of beer in the back.”
Leverage – in the US It still means to use a device to exert more force on an object.
Trolley – I think they use these in San Francisco?
Takeout vs Takeaway I can see and understand how takeaway is used and find it actually more accurate than takeout, although in the US taking something away means removing it without the person’s approval. “You takeaway your child’s Gameboy when they are being punished.”
Ridiculosity – okay you got us with this one, although I highly suspect the orator of this word was either being funny or did exceedingly poor in school.
Train Station? – It’s a station the train stops at, I fail to see the issue?
Scotch-Irish – Okay in the US both are known as heavy drinkers, need I say more?
Winningest – this word didn’t happen to come from the same person that used Ridiculsity?