>> What am I rambling on about?
OMG you ended a sentence with two prepositions, tsk tsk.
And you employed the "meaningless be" of the gerund like "I am rambling", as opposed to "I ramble" - a curious grammar construction inherited from Welsh and Cornish. Ever notice you don't hear that kind of phrase construction in Shakespearean English? It's a recent phenomenon. But I am digressing.
The differences in US/UK English aren't just lexical, they're also grammatical.
Use "inquiry". I'm Canadian, my colours have U's and a centre ends with "re". But "enquiry" looks weird to me, and we say "wrench" not "spanner". The advice about getting a Canadian to rewrite your text isn't a bad idea actually.