It's fixed in the only sense we can fix it: it won't show up in correct answers for multiple choice questions. Everything that is an accepted answer can still be shown to you as 'another correct answer', depending on what you input, that's just how the system works.
In English, "the" in "the girl's apple" captures both "the girl" and "the apple" (e.g., the apple of the girl). How comes it is not, then, "Flickans äpplet"???
That's actually not the case - the "the" is only for "girl", while the possessive "'s" is for apple. So flickans äpplet sounds just as bad as "the girl's the apple" would.
This is a good point - what if the sentence was distinguishing between a row of apples and selected the particular apple that belonged to the girl rather than describing it in another way? I'm not sure though that English would make this distinction without context, so maybe Swedish doesn't either.
If the sentence wants to know what 'the woman's' is in Swedish, this is a good tip. Remove ' 's' from 'the woman's' and translate it. (Kvinnan) Then take the apostrophe away then add it to 'Kvinnan'. Just a little tip to help.