Aimed Shots, p.30, Targeting Computer, p.113
In neither of these entries it's not explained how aimed shots are made against an immobile target in a presence of a Targeting Computer.
From TW p.143: If using a targeting computer to make an aimed shot against an immobile target, apply an additional –1 modifier (representing the targeting computer) to the –4 immobile target modifier. All other rules for an aimed shot remain the same.
Multiple Firing Arcs, p.27
Multiple Firing Arcs: Through torso twisting, a ’Mech with both upper-body and leg-mounted weapons may have more than one firing arc at once. Regardless of its number of firing arcs, a ’Mech may only have one primary target each turn.
The thing that I got from this sentence is that there can be only one primary target in a turn. I understand that a torso twist changes arcs... But was really meant by this sentence?
Indirect Fire, p.30
Pedantic comment about style. The entry lists modifiers under bullets, but then suddenly drops the habit before a start of the paragraph "Finally, if a spotter..." I suggest to make another bullet to list that final modifier. Also, a +1 modifier for weapon fire that comes from spotting in the same turn could be mentioned under Other modifiers in the Target Number Modifiers Section starting at p.25.
Piloting Skill Roll Table, p.54 and p.137
In Physical Attacks Against ’Mech and Unit’s Actions the word 'Mech is repeated needlessly and clutters the table. You can probably do without it.
Physical Attacks And Water, p.35
Partial Cover: Depth 1 water provides partial cover to a standing ’Mech against physical attacks. A physical attack made against a ’Mech in Depth 1 water by an attacker that is itself not completely underwater adds the +1 partial cover modifier to its Target Number. If the attack resolves to the legs, the attack is ignored.
From the underlined I understand that the kicks were not considered in this paragraph (because you can kick and kicks land on legs). A notion about kicks should be added.