Item resistances seem to be bugged.
I have a gal in grav harness in cold enviroment. She has a shawl, ushanka, durathred bra and space towel in her inventory, but she is still taking health damage. I'm pretty sure that's not supposed to happen.
Some ruleset digging revealed the problem: cold damage of the aura is damageType 18, while the resistances on the items is for damageType 17. Heat is now 17 while heat resistance on items is 16. So currently, cold resistance on items protects from heat, while nothing protects from cold.
I've corrected the values in Yankes_Scripts.rul, attached is the updated file.