Ashe and Crit Damage runes don't work

So i just ran a test of the new Ashe with her kit, and I wondered if slotting Crit Damage runes could bolster her new passive. I slotted all Mark and Quint + Crit Damage % runes for a total of 33% increased crit damage, and found that the total sum of crit damage is still only 10% more than the basic non-crit attack.

Is this intentional (and if so can I get a refund of my 9 crit damage % marks I just bought)?