Does the -35% Enemy Lightning Resistance on the Crescent Moon runeword and the Lightning/Fire-flavored Rainbow Facet help the Traps and FoF/CoT/PS do more damage?
No for the Traps (as the game considers them minions, they do not benefit from -x% Enemy Resistance), and yes for CoT/PS/FoF. Do note that while -(3-5)% To Enemy Fire/Lightning Resistance on Rainbow Facet does not work with Traps, ATM, we have not confirmed whether the +3-5% To Lightning/Fire Skill Damage on it does (though it has been confirmed not to work in SP). Both FB and SWeb are exempt from the above bugs/penalties, and benefit normally from Rainbow Facets (e.g.. both -% enemy resistance and +% skill damage work on them), as the game does not consider them true “Traps” (and by extension, they are not considered minions).