Ok, I've got some confusion over grappling and multiple attacks.
Lets say I've got a character with a +6 BAB and two natural attacks that may be made as secondary attacks. This means that a full attack routine would go: +6 (first main attack), +1 (second main attack), +1 (natural attack A), +1 (natural attack B). (Right? This is assuming that the creature doesn't have multiattack or similar).
Now, lets say instead the character is trying to initiate a grapple, and can do so with his natural attacks as well. Lets also say that his first attack was successful at initiating the grapple, doing the unarmed damage in the process. Is his turn over, or may he do something with the three remaining attacks? If he can use the remaining attacks, can he use them to make further grapple checks (to either do additional unarmed damage, or to pin, etc.)? In other words, are the three attacks wasted, or may he use them as normal for attacking in a grapple (and only attacking in a grapple), or may he potentially achieve a pin against his opponent with a single round? (i.e. first attack -> grapple attempt -> initiate grapple & unarmed damage -> second attack -> Grapple check -> pin).
Second question, this time regarding the feat/power Improved Grab. Improved Grab states that a creature may make a free grapple attempt after hitting with a natural weapon. Does this have the potential of doing double damage? If he hits with a bite attack (doing 1d6 damage), then gets his free grapple attempt, would a successful grapple attempt deal the same unarmed (natural) damage as normal on a successful grapple?