Real quick on point B. In the example of a gear pick granting multiple items (they use shuriken) it says "...the character may choose to place each of the miniaturized items in a separate Housing." The feat Magic Bullet states that a Gadget with multiple uses uses that number of bullets as Housing, I'd think that allowing the player to gain 2 molotov bullets with his Caliber I Gadget pick isn't outside the rules.
I concur on the other 3 points, though
That's correct, I missed the x2 when I glanced at the Cocktail's stat line. By the rules the character gains two Cocktail bullets per ammo load.
D) - You'd use the rules for multiplying, so you'd get 3x ammo, rather than 4x, but unless someone has more of an idea than me can't see any other problems with it.
Yeah. I was thinking that and that's the standard rule in d20... but I couldn't find it in Second Printing. That's why I phrased my reply that way.