How does grapple / grab / constrict interact with multiple natural attacks?

[Abraham Z.]

Boris Beastie has two claw attacks and the grab and constrict abilities. Round 1: he full attacks Pietro Pathfinder. The first attack hits, which gives him, via grab, a free grapple check, which succeeds; both BB and PP now have the grappled condition. Question 1: The grab itself doesn't do any extra damage but BB does now constrict damage from this first claw attack, yes?

Question 2: What now happens to BB's second claw attack?
2a: Does BB need to do another grapple check with claw 2 to maintain the grapple (still in round 1)? I assume no, because the grapple rules indicate that you have to roll to maintain the grapple each round, and BB has already successfully grappled in round 1.
2b: Does BB need to roll to hit PP with claw 2? If so, what happens if he hits? He does his normal claw damage but does he also do constrict damage? If he misses, I assume this has no effect on the fact that they are both grappled, yes?
2c: Alternatively, does BB simply get to do constrict damage with claw 2, without rolling to hit, because he has already grappled PP? And if so, does he do both his normal claw damage AND the constrict damage, or just the constrict?

Question 3: What happens in round 2?
Assuming that PP doesn't get out of the grapple on his turn, at the start of round 2 Boris still has him grappled so he needs to do a grapple check to maintain, but how does this interact with his two claws?
3a: If BB maintains the grapple, does he now do full claw damage and full constrict damage with both claws?
3b: If BB fails to maintain the grapple, is his turn over? Or can he now attack with one or both claws (possibly reestablishing the grapple if the claw hits and the grab attempt succeeds)?

I hope this all makes sense. I'm a relatively new GM and I'm running a game this weekend and it seems like this very situation may come up so I want to be prepared. Many thanks for any help y'all can give.

[Aydin D'Ampfer]

Grab:

Grab (Ex) If a creature with this special attack hits with the indicated attack (usually a claw or bite attack), it deals normal damage and attempts to start a grapple as a free action without provoking an attack of opportunity. Unless otherwise noted, grab can only be used against targets of a size equal to or smaller than the creature with this ability. If the creature can use grab on creatures of other sizes, it is noted in the creature's Special Attacks line. The creature has the option to conduct the grapple normally, or simply use the part of its body it used in the grab to hold the opponent. If it chooses to do the latter, it takes a –20 penalty on its CMB check to make and maintain the grapple, but does not gain the grappled condition itself. A successful hold does not deal any extra damage unless the creature also has the constrict special attack. If the creature does not constrict, each successful grapple check it makes during successive rounds automatically deals the damage indicated for the attack that established the hold. Otherwise, it deals constriction damage as well (the amount is given in the creature's descriptive text).

Creatures with the grab special attack receive a +4 bonus on combat maneuver checks made to start and maintain a grapple.

Constrict:

Constrict (Ex) A creature with this special attack can crush an opponent, dealing bludgeoning damage, when it makes a successful grapple check (in addition to any other effects caused by a successful check, including additional damage). The amount of damage is given in the creature's entry and is typically equal to the amount of damage caused by the creature's melee attack.

1) So, the constrict damage is actually 'from' the grapple, not a specific weapon. So when you use Grab to perform a Grapple Check and succeed, you also get the constrict damage.

2) You have options here. If you keep the grapple, and attack with the claw, you just do damage. Grab specifies 'start a grapple', so you cannot use it to maintatin a grapple. so:
a) No free grapple check to maintain, but not for the reason you gave.
b) Yes, normal roll to hit. Normal damage, no constrict, as you have not succeeded a grapple check. No effect on the grapple.
c) No constrict damage with claw 2 just for hitting.

3) You have the option to maintain the grapple, or full attack. Or move and standard.
a) Doing damage in a grapple is defined in the grapple options. It is not the same as a full attack. You choose which one-handed or light weapon to attack with, and do so after a successful grapple check. You would get a free constrict off this successful grapple check.
b) If you fail to maintain a grapple as a standard action, you lose the grappled condition, as does PP, but you still have all other actions (move, swift, free, etc).

Now, a few tricks you can do to maximize your damage and abilities(I'm adding some numbers, just so it can be followed):

Full round attack, two claw attacks(1d6+STR each).
1st Claw hits, deals 1d6+STR, free action Grapple.
Grapple succeeds, gain grappled condition, deal Constrict 1d6+STR
Free Action, drop the grapple.
2nd Claw hits, deals 1d6+STR, free action Grapple.
Grapple succeeds, gain grappled condition, deal Constrict 1d6+STR

You have just dealt 4d6+STRx4 over a single full round, and ended the turn grappling them. If they do not succeed their escape check, or don't try, you can then pin them next turn, or rinse and repeat.

Hope that makes sense. Feel free to ask questions, though, as grapple rules are crazy complicated, and often misunderstood.