Looks good! I'll go over the details of your character sheet more carefully, tomorrow. I don't have the character builder, but I don't think I need it: the information provided should be enough for me to figure out secondary stats with.
In terms of your character's background, I'm fine with most of what you presented. I particularly liked your addition of how Artico usurped your place. However, if you were thrown off a cliff as an infant, you wouldn't know who your parents are, or why you were tossed off a cliff. Therefore, it might be that your origins are different from what is presented. Your story would start with you being found by the sept's jarl. Of course, maybe there were clues. Perhaps the swaddling clothes provided a hint to your origins. Perhaps your mother went so far as to include a scroll with a written testimonial (maybe as a prayer of sorts) explaining why she felt the need to sacrifice you. In that case, you would certainly know your origins, at least if the evidence was to be believed.
If it's okay with you, I'd like to skip the part about the ritual adversely affecting your mind.
Concerning your birthmark: when you were born, the Cult of the Emperor was on excellent terms with the Church of Avandra, so that wouldn't have become a point of contention. The Cog of Erathis could get you into trouble in one of two ways: it could be interpreted as being the Cog of the Royal Sect; or its placement on your body could be taken as sacrilegious.
Other birthmark symbols that would get you into trouble:
The Hammer of Moradin
The Ruby of Asmodeus
The Eye of Gruumsh
The Serpent of Zehir
Symbology associated with demons or rebellious primordials
Whatever you decide, I do hope you're not planning for your character to drop his drawers in order to prove anything.
By the way, if you want to submit your character to public scrutiny, that's fine with me, but you always have the option of sending me your character's details through private message. All that the other players need to know is you're a half-elf barbarian.