Greetings, I assume I know the answer, but would ask for clarification. When I send my Guardian out to CC someone in ZoC, the enemy trooper may use CC skills, so can kill the model with Guardian, when it wins the FtF, right? Thanks:)
Yep, it increases the CC range for both models, but does not protect the user from taking wounds. And the enemy can of course use a BS ARO as well, which can also kill you.
During the active turn, you haven't used guard until after the enemy aro so they can't aro cc, or is guard automatic?
Rules as written, it seems that if you declare your CC attack with guard as your second skill, the opponent can not CC you because he had his change to declare an ARO after your first skill. So as an answer to OPs question: Not with cc attack, but there is nothing preventing the opponent from ftf shooting you.