I'm sorry if this is a dumb question, but I just downloaded KVS' tool and am trying it out. If I want to determine which airlines/flights have seats available for reward tickets, is it safe to say that if the class starts with an 'X' that means I could get a reward ticket in coach class?

Is there a good listing of various airlines reward class codes?

Also, I saw one airline which listed a class 'X2'. What does the number following the class mean?

Thanks for bearing with a newbie!