Okay, lets say my Witch hunter warband has an infected Flagellant who has just been charged by a dual wielding Dwarf Beardling (2 hammers)
Step 1 - Beardling rolls 2 dice to hit needing 4s; rolls 4 and 6
Step 2 - Flaggie is T4 so the Beardling needs 5s to wound; rolls 3 and 6, yielding one critical wound
(Here's where things get dicey)
Option one The flaggie fails his Ld test and becomes the Balewolf, the Balewolf's T is 5 and therefore the 6 was REQUIRED to wound and therefore is not a crit, so one wound is caused to the Balewolf (if he fails his armor check), he has 2 remaining and we move on
Options two, three and four Crit was determined by flaggie's T so we roll result of the crit wound
Step 3 - For the crit result we roll 3, so "two wounds, no armor save"
option two con't two wounds are caused against the Balewolf and we move on
option three con't two wounds can be saved by the balewolf's "armor" as it states no effects can reduce it, unsaved wounds are inflicted against the Balewolf and we move on
option four con'tor finally the two wounds are inflicted against the flaggie and an injury roll is made.
The last bit is if option four is correct and anything but an "out of action" result comes up does the Balewolf suffer the same fate?
grab two models, the rules for the Balewolf and imagine the "charged" model is infected, run 2 or 3 combats and you'll quickly see my confusion...