Complex sentence: The script ran into difficulties after accusations from Eon Productions that the project had gone beyond copyright restrictions, which confined McClory to a film based on the "Thunderball" novel only, and once again the project was deferred.
Split into simpler sentences: The script ran into difficulties after accusations from Eon Productions that the project had gone beyond the restrictions on copyright. These qualms limited McClory to a film based on the novel "Thunderball", only, and once again the project was deferred.