There's plenty going on here so this is a bit of a catch up for me. (Edited following having been beaten by a shorter reply!)
Firstly, to answer some of Laurence's original points:
1) There is no "Rules Team" associated with this site. There is a team of authors who can produce Errata to cover mistakes in the original rules. In the past they have also created FAQs to cover general areas of misunderstanding. These are the only official changes/interpretations of the rules. Some players like to report incidents that happened in their games that they have found unclear and a number of us are prepared to offer opinions based on our understanding to aid in dealing with a similar situation should it arise.
2) As Graham said regarding the completeness of the rules, they will cover the vast majority of situations that will be encountered in a normal game. What you will often see here is something that is new to people who have been playing these rules for 5 years or more. They are thus sufficiently rare that you are unlikely to encounter them. However, should something arise then in a friendly game you can come to an amicable solution with your opponent or, in a tournament, call on an umpire. I think that it would be unfair to expect all of these incidents to have been anticipated and covered without the rulebook being massive (and probably constantly on draft form).
3) It is my belief that these unusual situations where they do arise are either based on an unfamiliarity with particular area of the rules (the recent discussion on Battle Wagons/Artillery largely resulted from the widespead opinion that these troop types are rubbish so most people don't use them or know the rules about them) or a situaton that is specific to the game in question. In the first of these the solution is clearly to go back to the rules, in the second any decison can only apply to that game and should not be regarded as a precedent for something that looks similar. For that reason I am strongly opposed to use of the "Clarifications" which I consider to have been a bane of previous rulesets and do not wish to participate in introducing them to FoG, although I am grateful to Hunter for his confidence in my abilities
I am of course happy to continue to participate as an enthusiastic amateur in helping people to find solutions to issues that they struggle with because I enjoy playing both FoG AM and R and would like to see them continue. So to consider Zoltan's examples with a bit more background in how I look at them may be useful. (Or not!). So, on to the example:
For me this is covered in the rules by P9-7 (digital version, P67 in the book according to bbOtus). This states that a charge that does not qualify as a flank charge can contact a flank edge if the target base is not counted as being in melee to its front. Specifically this "is treated as a normal charge on the enemy front". So I would regard both of Zoltan's examples as the same as a flank edge has been contacted by something not counting as a flank charge. So, in Impact (assuming open terrain, no cohesion issues and as summarised by bbotus):
The Cavalry (2 bases) have hit 2 enemy bases, therefore both sides will fight with 2 bases.
The Cavalry get + for Lance and + for fighting MF in the open.
The MF get nothing as there is no Impact POA for Javelin.
So the Cavalry get 4 dice at ++, the MF get 4 dice at --
The MF however have LF bow who are entitled to shoot in support at impact. The Cavalry are Unprotected in more than one rank so this wil be at + POA.
As thus is treated as a normal charge on the front, both MF bases are counted as such and therefore are entitled to 1 dice support shooting from the rear rank. However, as the rear rank is LF this is reduced by 1 dice per 2 so they only get one.So, in summary:
Cavalry 4 dice at ++
MF 4 Dice at --, 1 at +
Some people have an issue with this as it appears that some bases are being counted twice (and indeed it would be further complicated if the MF were bowmen where a second rank base can appear to be fighting as a front rank and providing support shooting to both the actual front rank base and itself) so in these cases I believe it is helpful to pay less attention to the tabletop depiction (i.e. the bases and toy soldiers on them) and more to what is being represented.
The configuration of the MF BG is such that the MF are in optimum formation for fighting (indicated by being 2 bases deep, the most that they will get benefit from in the rules) with a thinner rank of bowmen to provide support by shooting overhead. The width of the formation is indicated by the frontage of the bases, but it is known that the depth of these is proportionately much greater than would be necessary for the frontage due to the size of the figures used. So the bases give a general indication of the location of the BG but I would regard the situation where the cavalry have hit a front corner of one base and stepped forward into that behind as being one where the actual position of the infantry formation is a line approximately from the front of the leftmost file to the back of the right hand one, i.e. a diagonal line in the optimised fighting formation. So a charge that doesn't count as a flank charge (for which the rules are pretty clear) hits the front of this line and therefore the combat is calculated accordingly.
I think that the other major consideration when trying to resolve these issues is to consider the effect of the alternative. In the situation where a 2 deep formation of MF with Bow has been impacted on the front corner and the chargers have stepped forward into the second rank base, the obvious other interpretation of a scenario like this would be that:
Both MF bases fight at --
The first rank base does not benefit from support shooting as the base behind it is fighting
The second rank bas does not beneft from supprt shooting as there is no other base to provide it
The outcome of applying this interpretation would be that there is an avantge to be gained from charging a front corner and stepping forward into a second rank base, thus creating a new type of partial flank charge in addition to those provided for in the rules which are Front, Flank or Rear.