Methodologies for systematically including configuration states in calculations for atomic transitions in many-electron systems such as nitrogen are explored. Instead of generating configuration states by replacements from a reference configuration, promotions from a reference complex are considered and the notion of layers is introduced. Our methodology provides for an effective strategy for handling systems with many electrons in a partially filled shell. Theoretical transition data is reported for transitions among a number of low-lying quartets in nitrogen. Comparisons with known experimental data and other theoretical calculations are included.