Rivfader Csihar's page

The item as listed here indicates a +1 bonus to attack and weapon damage rolls. Stalker's Mask
However in my Anniversary Edition of RotRL it is listed in the appendix as a +2 bonus on both counts. The rest of the entry is identical. Can someone point me in the direction of some clarification?

So the r.a.w. reads;
When in doubt about whether two characters flank an opponent in the middle, trace an imaginary line between the two attackers' centers. If the line passes through opposite borders of the opponent's space (including corners of those borders), then the opponent is flanked.

So if you have this layout, each number representing a 5ft square;

1|2|3
4|5|6
7|8|9

My question is if 4 flanks with 3, 6, and 9? Or only square 9.

The Alchemist in my group thinks that when he hits a large creature with his bomb than the creature will take splash damage in each of the squares that was not hit with the bomb.

Example; large creature takes up 4 squares =

|1|2|
|3|4|

The alchemist hits square 4 with a bomb for 2d6+4 and then splashes squares 1 2 and 3 for 6 damage each. That would be (2d6+4)+18 fire damage per hit. It seems unreasonable to me, and I'm pretty sure the large creature should just take the 2d6+4 and would not be included in the splash damage, but I cant find anything in the rules to support this. Any suggestions?