Yup, the miles earned for each segment are based on the fare code for that segment. The full fare rules show 100% for the flex segment and 50% for the lite segment when I did a test booking.

However, the restrictions and penalties for the entire ticket are based on the most restrictive segment e.g. you can book a Flex outbound that can be cancelled with a $100 fee with a Lite inbound that is non-refundable; however, the whole ticket is now non-refundable. Re-booking also goes from free to one with a fee even for the Flex segment.