It is very similar to MoE. You can attend both, one or no sessions. Your best time of the two sessions is your qualifying lap. If you do not attend the sessions, you start from the back.
Thats how it works as far as I am aware.
Regarding the Blend lines, the first bold section regards pit entry, the second relates to pit exit.
IRC is there so that we can get into contact with you. You will only be penalised if we need to contact you and no-one is avaliabe. You have the choice of putting a man in there or not, your risk. I had IRC and TS running for the IGTC round just to show that we had a representitive until Jackson came, it still works, although you clearly can't send or recieve messages.