Превод - Японски-Английски - 手にしたボトルにメッセージをつめて そっと海に流したの

I suspect this is correct, but it doesn't agree with the French translation - "stuffed" is not "glissé"!

Ian, are you translating directly from the Japanese version? I´m asking because your translation is quite different from the Portuguese, Brazilian-Portuguese and French versions (they don´t say anything about the "I had gotten hold of" part)

I'm guessing that Ian translated directly from the Japanese, as he speaks Japanese fairly fluently.

Yup, here is literally what the Japanese says:
I had gotten into my hands (i.e. had managed to find) a bottle, I stuffed (i.e. with a little effort, that's what the Japanese verb "tsumeru" means, like stuffing a teddy bear or a turkey) a message into it, and then gently put it into the sea and let it float away
Other language translations may have been done from the French, I suspect...
But I'd be happy to answer any questions about it...

fairly fluently...

Botica, do we need to change the French version because of Ian's note above?

CC: Botica

Yes I think the translation I've accepted is not complete.