They don't have different meanings, but they link different parts of the answer. The full answer is:
If you can't use girl, you could try (definition of lass). This is probably borderline archaic or dialect-dependent, however, but other terms are that as well: maid, maiden, lassie, colleen, etc.
The however stands between the first sentence of the answer ...
Completely idiomatic. A moment's googling finds many examples of this exact sentence:
"I think you know my brother, Frank, he lives in the same building as you," he replied. So that's how he knows about me. Through Frank. So Frank talks about me to his brother? Interesting.
Three things contribute independently to the great success: money, attention, respect.
I think the use of "with" here awkward.
I think poorly written sentences are not good ones for practicing how to parse English.
The sequence of words and am an English is difficult to pronounce.
Few English language speakers would use it.
Although you could use the constructions you suggest, they are not idiomatic.
Much simpler and more natural would be:
I am from Asia and I'm learning English
Or, less likely:
I'm learning English and I'm from Asia.
Another possibility - with ...
Part A should be attached to part B while part C remains attached to part D.
Part A should be attached to part B with part C (being) attached to part D.
I know "with" has a usage similar to that of "while", but unsure how they differ. For the above two sentences I created, I would like to know which is correct.
Both are correct and ...
Sentence 2 is not correct unless you remove the parentheses around 'being.'
With that said, Part A should be attached to part B, while part C remains attached to part D and Part A should be attached to part B, with part C being attached to part D mean the same thing.
A comma separates a list of more than 2 items. Your examples only have 2 items in each sentence, so can't use a comma.
Visually, the problem with your examples is that without a comma, it is confusing with too many "and"s. I usually try to use "&", so it becomes "the correlation between A & B and that between C & D are ...