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-formalism, which is exclusively based on a new form of velocity-dependent gravitational potential energy. The present paper is actually an additional exploration, exploitation and extension of the CGA with the main aim of showing (1) the Galilean invariance of CGA-equations; (2) that the CGA is in a certain manner a metric gravity theory; (3) the existence of an important similarity between the CGA and General Relativity Theory; (4) a new CGA-formula for perigee and perihelion precession is derived and proved to be in excellent agreement with observations; (5) the CGA-effects on orbital motion inside and outside the Solar System are investigated; (6) the conversion rate of orbital energy into gravitational power radiation is calculated and its effects are studied.