Combined Gravitational Action (V): Extension

In series of papers relative to the Combined Gravitational Action (CGA) as an alternative gravity theory, we have developed the CGA<i>-</i>formalism, which is exclusively based on a new form of velocity<i>-</i>dependent gravitational potential energy. The present paper is actually an additional exploration, exploitation and extension of the CGA with the main aim of showing (i) the Galilean invariance of CGA<i>-</i>equations; (ii) that the CGA is in a certain manner a metric gravity theory; (iii) the existence of an important similarity between the CGA and General Relativity Theory; (iv) a new CGA<i>-</i>formula for perigee and perihelion precession is derived and proved to be in excellent agreement with observations; (v) the CGA<i>-</i>effects on orbital motion inside and outside the Solar System are investigated; (vi) the conversion rate of orbital energy into gravitational radiation is calculated and its effects are studied.