Been experimenting for a few days now, but I can't seem to find a pattern or definitive reason that can change a unit from say a Line Infantry to Skirmisher.

My changes include adding or removing abilities in the unit_to_unit_abilities_junctions_tables and unit_class_to_unit_ability_junctions_tables
changing unit class in the units_tables
setting the unit_drill_set in unit_stats_land_tables to various settings.
adding/removing officer, musician, or standard bearer (Which yields the best results.)

My goal for my mod is to allow Guard Infantry to fire like Light Infantry when they're in tight formation. Mass Fire I can get to work and its decent, but not all the units fire and it works best when the unit has a little more spread in their formation.

The first unit I edited, Cossack Infantry, after removing the musician and standard_bearer became a skirmisher unit fairly quickly. I also converted the late_riflemen unit into a line infantry type rather easily by adding a drummer musician, adding rank fire abilities and changing unit_drill_set (if it even had an effect on it).

So it kinda perplexes me why Guard Infantry are giving me so much trouble when on paper (in the mod pack) everything is set up for them to be light infantry, minus light infantry tactics (Which giving them said ability results in the weirdest Rank Fire.)

P.S. Even giving them Mass Fire is a hassle, but at least do-able.