Hi Dawn,
I've looked over Debretts and every other 'nobility' guide I could find, but none of them mention anything other than her name and the fact that she was naturalised by this particular Act of Parliament.
I'd love to know more as she must have led a fascinating life. She was obviously born abroad, moved to England and married Sir Robert (oops, in my first post I accidentally said Sir George - I meant Sir Robert).
They then moved to Paris during the French Revolution, moved in the right (and wrong) circles, before Sir Robert ended up in a French prison. He avoided the guillotine but died in Paris in 1802. Charlotte stayed on in Paris, dying in Versailles in 1823.
A fascinating period of history and she was obviously at the thick of it.