(a) This rule shall apply to any action for custody, partial custody, or visitation, whether filed as an independent cause of action or as a count in a related proceeding.(b) Upon the filing of any complaint, petition, or motion relating to child custody, partial custody or visitation, in which there is no agreed-upon Order disposing of the issues, the case shall proceed in accordance with Pa. R.C.P. No. 1915.4-1, et seq., and these Rules.