Firstly, if you're a Primarch, I'm the God-Emperor's mother.
Secondly, if your character is from any chapter other than Black Templars, Blood Angels, Dark Angels, Spac Wolves, Storm Wardens, or Ultramarines, we'll be doing this sans-dice, as those are the only chapters with rules thus far.
Thirdly, I believe there is a link to the PDF of the Core book somewhere in the Table-Top Tyrants' group. Not sure which discussion, though. Probably in the one about Deathwatch, though it might be elsewhere.