First I would like to say that I am no expert on SM combat system and am just trying to help you out.
Some of my notes: I am working off ICE's PDF copies of the SM2 rules [It also says in the beginning of the Chr book that the original SM1 Tech Law and Future Law are not compatible.]
1) page 53 of the players book; section 13.1 second column: It essentially says; Some weapons can fire more then once in a round and are provides two rolls to represent this.
a) After some looking this is represented by the rate value on chart 1 page 65 of the Tech Book. It lists either a 1 or 2 and the type of fire the weapon may do.
2) Section 13.0; says that this is a modified RM1 system which is a preview [my word] of the RM2 combat system. And goes on to say; Missile weapon take a 50% attack % time and not 75% as in the previous RM1 rules.
3) In 13.2 under the heading OB Penalties for Moving/Maneuvering it states first sentence, "
If you fire in Fire Phase Phase A......"
IMO it seems to allow for two distinct attacks for weapons that have a rate of fire of 2. Each of these attacks which take only a 50% action receive full OB, unless you have done something else in the round. If you do something else besides fire your weapon you receive a penalty to your action.
Round:
1) Psion Action
2) Psion results
3) Prion Orientation
4) Fire Phase A
5) results FP A
6) Movement
7) Fire Phase B
Results FP B
9) Melee Phase
10) Melee Results Phase
11) Final Orientation Phase
My logic:
1) If you can fire in Fire Phase A [FP A] and fire in Fire Phase B [FP B] then that equals 100% activity.
2) Any activity after FP A if it is a move or a Moving Maneuver is penalized as if a 50% action has occurred. Those actions happen in later phases.
3) Movement Phase comes before Fire Phase B, so if you move you will have penalties to firing in FP B.
Basically what I take from it is that if you fire a weapon in FP A you have 50% action remaining. MDC