Any time I try to compress a star (or planet) into a neutron star, the nova happens and the pulsar/neutron star forms and then gravity stops working. Bodies in orbit go off in a tangent and cannot be affected by gravity again. New bodies are also unaffected by gravity. This happens with black holes too sometimes but not the last time i played (about 10 minutes ago). Also, I tried recently to form a compact star from the sun and got a white dwarf Sun Nova Remnant but no supernova; it still had gravitational effects though.