Your Codex is very detailed and has obviously had a lot of work done on it.
There are some minor things however:
- Krillak Magnata: you accidently call him Cortan in his fluff blurb. Also, Vulkan wouldn't give him a weapon he made just because he didn't like it. That doesn't sound terribly heroic, may I suggest instead that you change it to something like
that he was given it for saving his Primarch's life on the battlefields of *this place*.
- Nighklanus: his special force weapon rules are a bit confusing; do you mean that he can use it twice a game unlike most other force weapons?
- Infantry Sergeants: the Promethean Squad Sergeant has WS5 and the Drake Flame Redeemer Sergeant has WS5, two wounds and artificer armour! Don't you think that is a little too powerful?
- Fire Drakes: In my humble opinion they don't really belong in the troops section. Maybe you could include a special rule saying that if you take Rapheus Kane then you can do so.
Otherwise an interesting project!