I consider question 2 answered by the posts of Jackinator and imintdead, and I share Tau22's feelings on the topic.
However, the issue of TS Dreadnoughts is far not concluded in my opinion.
If you look carefully, you find that the effects of the Rubric of Ahriman are not all too detailed. I quote: "The results were not what Ahriman wanted, much less expected. The Thousand Sons were now safe from the taint of chaos, but at a terrible price. Those who had psychic powers were greatly strengthened. But those who hadn’t had their physical bodies reduced to dust and their souls were damned to live inside their armour forever, changing most of the legion into Rubric Marines; little more than mindless ghosts."
This hints that not only the Marines were affected by the spell, but the Legion as a whole
. Now you could argue that not every Marine had his PA on when the spell was cast, but you could rightfully say that such minor issues are of little concern to the Lord of Change. The supporting crew, who were not Marines at all? They're not relevant neither to the spell, nor the concerns of Ahriman; he was interested in saving his brothers, not the maggots serving them. Tank crew? Well, since they're waring PA too (correct me here if I'm wrong, I'm bluffing to be honest
), the effects of the Rubric should apply to them as well (technically, you could treat the crew as Rubric Marines).
But what happened to the Dreadnoughts? It would certainly raise an eyebrow that they were the only ones who were not affected by Ahriman's sorcery. Consequently, they too had the remains of their bodies turned into dust, their will bent to that of their sorcerers and their emotions dulled/torn out from them. This logically means that Thousand Son Dreadnoughts should not have the Crazed rule, for this very reason. I wouldn't consider this game-braking or anything, since GW could easily make the restriction that they could only be deployed in a Thousand Son army that has a Sorcerer or a Tzeentchian Chaos Lord.
What do you think?