The more I think about this the more complicated it seems.
I like to play in army-by-army mode, the most complicated movement rules, because I think that that is one of the most innovative and exciting aspects of the game engine. I hope to see more of this kind of device in future games . . .
Lets say I'm Germany and I use I and II Army to attack Longwy in early August and achieve a breakthrough to attack the next one south (Montmedy?). I set I Army as main army activate it, coordinate II and attack. I win pushing French out of Longwy and get my breakthrough attack into the one south of Longwy (Montmedy?). Lets just say for example that I win that one too, so I have just pushed deep into French territory in just a week or two of time. Indeed, if you consider that I still have several other armies that can follow up on these initial moves by I and II Army, maybe the Longwy-Montmedy push really only took up a week or less.
I'm not certain about this, but given the whole "home before the leaves fall" six-week victory plan, I'd think that the German plan would have been that the rails in those initially occupied territories would be pretty much immediately converted?
Maybe it would be too fast, but shouldn't it be possible for I and II Army to now convert the rails in Longwy and Montmedy BEFORE the end of the Early August turn? Thus allowing units that (in army-by-army mode) move AFTER them (a couple days after) during the same turn to benefit from the conversions?
The current system I think would allow this, although it doesn't work quite right in allowing rails to convert even when the combat to take control of a hex is not won.
Unfortunately, changing it so that conversions cannot happen by attacking armies would eliminate this "primitive" blitzkrieg (PB) possibility in army-by-army mode. It had not dawned on me but it is necessary that conversion be possible by armies moving INTO an enemy controlled hex in order for this PB dynamic to actually work.
Thus, Calvinus, I understand what you are getting at when you say
1) Conversion takes place only if no battle has taken place. I will try to do the conversion is performed at the end of the battle, in case of victory, but I'm not sure it can be done... I have to study the code before.
I hope you can get it to work this way:
1. If a friendly unit is in a friendly converted-rail hex or friendly non-rail hex and is adjacent to hexes with unconverted rails, and has enough MPs to move into one of those adjacent hexes plus the conversion cost, then the convert rails button may be turned on prior to moving. If the destination hex with unconverted rails is friendly controlled, then the rail conversion happens immediately as the unit moves into the destination hex.
If a unit with rail conversion turned on moves into an enemy controlled hex with unconverted rails, rail conversion can happen under two conditions: (a) if the destination hex is unoccupied, or (b) if friendly units win the ensuing combat for the hex, and the unit with convert rails turned on ends the movement and combat with sufficient remaining MPs (1 or 2) to carryout the rail conversion.
2. If a unit starts its turn in a friendly controlled but unconverted-rail hex and has at least 1 or 2 MP, then the convert button can be clicked. In this case, when convert is clicked, the hex immediately converts, and the unit loses the conversion cost MPs. Any remaining MPs can then be used for movement and/or conversion in adjacent hexes.
3. All controlled, but unconverted hexes are converted automatically at interphase, i.e., without any unit actions and even without any units occupying the unconverted hexes.