Do I get any additional benefits for example lounge access, priority seating, additional baggage?

The partnership with bmibaby is a pure miles based relationship, therefore the above additional benefits do NOT apply to Diamond Club members travelling on bmibaby operated flights.

Am I entitled to complimentary food inflight?

bmibaby does not offer complimentary food inflight.

As an existing silver/gold Diamond Club member, will I receive a monthly loyalty bonus for my bmibaby flights?

Yes, bmibaby flights will qualify for the monthly loyalty bonus that Diamond Club Gold and Silver card members receive.