Actually, pdb, the tickets have been issued as I originally requested them. LHR-IST-LHR is OK along with CAI-LHR...LHR-CAI. There is no need to buy extra segments. The "deep Europe" restrictions do not include Turkey.
There is no requirement to have a through flight from SWP to Europe. A transit via Asia is specifically allowed in the OWE rules. Thus, my AKL-HKG-LHR segments have been issued, open, with the appropriate x/o notation.