[Warrenkicker]

(NF rules from 2005 rule book, rule numbers or article numbers and sub-letters may have changed.)

Rule 2-6
ART. 1 The ball is ready for play when, after it has been placed for a down, the referee gives the ready-for-play signal. The 25-second count shall then begin.
ART. 2 Action or inaction which prevents promptness in putting the ball in play is delay of game. This includes:
a. Failure to snap or free-kick within 25 seconds after the ball is ready for play.
b. Unnecessarily carrying the ball after it has become dead or consuming time in failing to unpile at the end of a down.
c. A coach-referee conference after all the permissible charged time-outs for the coach’s team have been used, and during which the referee is requested to reconsider the application of a rule and no change in the ruling results.
d. Failure to properly wear legal or required player equipment when the ball is about to become live.
e. Snapping or free-kicking the ball before it is marked ready for play.
f. Any other conduct which unduly prolongs the game.

PENALTY: Delay of game (Arts. 2a,b,c,e,f; 5) - (S7-21)

So it is illegal and is delay of game if the snap (or free kick) happens prior to the RFP.

As for rotating the ball prior to the RFP, the snapper might not be allowed by some umpires to even touch the ball prior to the RFP but that is up to personal preference. But touching the ball prior to the RFP is not illegal.

Rule 7-1
ART. 1 The snapper may be over the ball but his feet must be behind the neutral zone and no part of his person, other than a hand(s) on the ball, may be beyond the foremost point of the ball.
ART. 2 The snapper may lift the ball for lateral rotation but may not rotate end-for-end or change the location or fail to keep the long axis of the ball at right angles to the line of scrimmage.
ART. 3 Following the ready-for-play and after touching the ball, the snapper shall not:
a. Remove both hands from the ball.
b. Make any movement that simulates a snap.
c. Fail to clearly pause before the snap.
d. Following adjustment, lift or move the ball other than in a legal snap.

It does not specify when the ball can't be rotated end-for-end in article 2 but in article 3 they specify only after the RFP so I would say that rotating end-for-end is never allowed.

And as for your last question about what the down and distance will be since the foul occurred before the RFP the chains had not been officially set and will be reset to the new position.

5.1.2 SITUATION E: Fourth and 2 on B's 25-yard line. A1 is tackled at the 26, short of the line to gain, and B2 then piles on. RULING: The referee shall signal a change of possession by signaling first down toward A's goal. The penalty for B2's dead-ball foul is administered and the line-to-gain equipment then set, making it first and 10 for B from its own 13-yard line. COMMENT: On fourth-down plays, A must get a first down by virtue of the yardage gained, including any yardage or an automatic first down from penalties for player fouls during the down, or it is a new series for B automatically when the down ends unless the down is to be repeated. The penalties for all unsportsmanlike and non-player fouls which occur during the down in which a new series is awarded, and dead-ball fouls prior to the subsequent ready-for-play signal, will be administered before the new line to gain is established and the chain and box are set. In all cases it will be first and 10 for A unless it is inside the opponent's 10-yard line. On plays other than on fourth down, A may gain a first down by virtue of the yards gained or from penalty enforcement.