NVM I found it. So I'm assuming these modifiers are for the model's RC stat? If MR= 3 that means + 3 to the model's RC? And -3 means subtract 3 from the model's RC?
P. 121 - right under section 7.
Weapon Effects effect DM, not CC/RC. Special abilities, Cover, Aim, Weapon Bonus/Penalties, etc. affect RC/CC. (CC 1, SR 1/2, etc.).
The effects are rather easy to understand. Certain models take extra damage from certain effects. If a weapon has more than one effect, it ignores effects that would stop it, unless all effects are affected; i.e.: If a
Ballistic, Rending attack hits Ablative Armor, the Ablative effect is cancelled, because the
Rending effect still exists. However, if that Ablative Armor is struck by a
Ballistic round, the Ablative Armor decreases the DM by 1.