On the matter of KE's system saying no mileage credit to KL, I'd bet it has something to do with the booking class changes and KE not updating their systems to show which fare classes earn in FB now.

For status updates, it seems that your status at ticket issuance tends to be what sticks with in partner systems. Note that if your ticket is reissued (think schedule changes) between purchase and departure, it might pull your new status.