Chaos Psychic Focus and thousand sons. (Page 22 big rule book)

[Charon]

As he may ROLL up to half, he is perfectly fine with having 2 powers (actual wording). So it does not violate the rule in any way.

And even if you would rule it out, the Scroll of Magnus would instantly invalidate the character as it does not state an exception to the general rule.

[Xaric]

Scroll of magnus generates powers as per turn when you use it the rule about half the powers is referenced to the start of the game and yes the reason I said you get it was the principle of CSM generating 2 powers when they can only have half the powers rounding up of there god and half of 1 is 0.5 rounding up is 1 power so this rule is extremely contradicting iver you don't have to take a power because of the chaos focus giving you that swap power for free or you allow the CSM psyker to generate more then half the powers you cant have it both ways or that would be counted as a double standard...

[Charon]

As I said (with the actual wording) its not contradicting as the same wording (roll) is used.
So a level 1 is forced to roll up at least one power of ttheir patron god (check) but may not ROLL up more than half (check, he just rolled ONE). So no double standard here, in both cases the wording is "roll".

[Xaric]

ok I am agreeing with you now Charon that does make a lot of sense