Okay, finally got some screenshots. Earlier today I only got to play for about ten minutes before I had to leave the house, which amounted to just as the lines met at the Battle of Raphia. So anyways I just decided to start a new campaign for when I actually did play, and here's the results.
Campaign is on the BI exe, H/H, 0 turn recruitment, as the Ptolemies.
First thing I notice is...
1001 Denarii for the richest faction in the Mediterranean? Presumably a bug, especially since I checked out the Greek Cities and noticed that they start with 100,000 Denarii. Anyways, I just ignored it and accepted my first turn as 'lost' as far as building went, so I went around changing taxes to my liking (High, as recommended somewhere in the economy thread), and disbanding troops I didn't feel I needed. I also noticed that the Ptolemies don't start with any ships or navy, which is inaccurate both because they probably had the best navy of the Eastern Mediterranean at the time, if not of the entire Med. And of course it's also annoying from a gameplay perspective since they have overseas territories. Presumably it was just overlooked?
Before I ended my turn I made the faithful decision not to attack Antiochus at Raphia, and wanted to see if he would attack me and thus give me both the advantage of a defense and, I believe, would also be more historically accurate (though that is foggy at best). Unfortunately Antiochus decided he didn't have the testicular gumption to do so, and retreated back to Hierosolyma (Jerusalem nowadays at any rate), which was problematic because now not only would I have to attack him, losing my hoped-for advantage, I'd also have to contest with the 1,000 man garrison in the city, which would erode my advantage in numbers.
One last thing before I get to my experiences on the battle field.
Typo? It's the same way with the Kleurochoi Phalangitai, but not the Pezhetairoi or the Levy Phalanxes, who both are Primary Armor = Leather. I'm not sure if that has any bearing as far as gameplay goes, but its something that should be fixed if nothing else because it looks silly and is obviously a mistake.
Anyways, next turn I queue up a bunch of roads and other basic things for my settlements once I get the massive influx of cash due to any self-respecting Nile-based faction, and advance to stand Ptolemy with his army beside Antiochus, end turn, and find that he still won't budge so on my third time I finally besiege Jerusalem with the intent to withdraw as soon as Antiochus moves to defend his city in an effort to 'dislodge' him. It worked, but my army retreated in a stupid way and went around to the other side of the city (North East), and Antiochus cleverly went even further around and oriented himself so that Jerusalem's garrison attacked me from the South West while he came at me from the North East. Great. 
The battle commences and, thank goodness, Antiochus' reinforcements were delayed so I only had to deal with him at first.
The battle is joined briskly enough, my Elephants charge into Antiochus' center phalanx in hopes of disrupting the formation before we clash (No such luck. The inferior Egyptian elephants performed pathetically, getting skewered on the end of Antiochus' phalanx while only killing a handful of his pikemen. That outcome was what caused me to be really surprised at this next picture.
Incase it's not immediately evident, the Seleucid Hetairoi charged straight into my wall of Levy pikemen (at first I thought I was fortunate), and proceeded to simply plough them, forcing the wall of phalanx and spearpoints to go concave. As you can see in the screenshot they've managed to kill between 140 and 170 of my levy pikemen at the cost of only 20 of their own number. Notice that they're destroyed one unit, but at the same time fighting the flanks of two other levy pikemen units (one is pictured, the other is off to the right a bit more). In the lower left King Ptolemy rushes in with his bodyguards from the extreme left flank of the line, and rides to the relief of his embattled soldiers. Unfortunately, the Seleucid Hetairoi not only manage to route the entire right flank of my phalanx, the also kill the King and eventually send his bodyguards on their way screaming for the hills. Daaamn.
A few moments later the rest of the pikemen on both sides of the battle clash. Antiochus sends his lighter troops in with the pikemen to engage my more higher-end pikemen. My Thracians, Celts, and Arabs are all but destroyed at this point, but they absorbed and killed the Seleucid elephants on the right flank, just a little ways away from the above picture.
Even with the invincible Seleucid Hetairoi (it turns out that Antiochus, with his cataphracts would pull the same stunt more towards the center of my Phalanx-line with similar results) I felt that I could still win, since my Libyan spearmen and Royal Guard were unopposed on the left flank and were free to advance and envelope Antiochus' right flank engaging my Royal Pikemen and the Pezhetairoi (I had aligned my phalanx with the higher quality troops on the left, and they descended in quality going to the right). Well this is how that worked out.
You can see here my Royal Pikemen on the left, struggling against crappy Persian Spearmen levies. As you may notice, at this point the battle is basically over (entire army routed besides the two units pictured), so at this point I was continuing for merely academic reasons. Also, they're hard to see, but the right most of the two Ptolemaic banners in the picture is the royal guard, who are behind the Persian Sparabara. Disappointingly, the Persian Spearmen did not rout, and were not quickly destroyed by my armies two elite divisions, which I took as quite a surprise. Indeed they held their own into the inevitable onrush of God-Cataphracts and the 'Seleucid Immortals' (what I call their Hetairoi) rushed in to rout my last surviving units. This was very annoying and, I feel, unreasonable. These probably ill-trained, ill-motivated Persian levies were able to stand against a crushing phalanx from their right, and a squadron of Royal Guardsmen from behind. You can't see it in this picture, but there used to be a unit of Pezhetairoi in the front of the Sparabara before the neighboring Seleucid Agyraspidai's routed them.
As it turns out, Antiochus didn't even need the reinforcements from Jersualem to win the day, they only arrived just in time to mop up my two Royal regiments who, at least to their credit, were the last to rout.
Here are the battle results. Look closely at the casualties-caused figures. If you notice, the Cretans appeared to have carried the day, though gratifyingly the Royal Pikemen (incase you all haven't figured out what I mean by that term, I'm referring to the Ptolemaic Kleurochoi Agema) also at least managed to get their kills into the triple digits. This is because they ran into some lightly-armed trash unit, and routed them near the start of the battle before they turned and, as pictured, began to engage the Sparabara alongside the Royal Guard.
Pathetically, you can also see that the majority of my pikemen regiments caused casualties in either the teens or the twenties. This is particularly disconcerting because throughout the battle they had heavy cavalry charging into their spearpoints, and in what places the infantry did manage to engage my enemies' infantry the resulting clash looked very brutal (you know how it gets when two phalanxes close together on one side and look like the only way it's going to end is with a few hundred dead?). Very disappointing I must say.
In conclusion I attribute this lost to several different things, some my fault, but also some things that I feel are probably genuine flaws in the balance of the game.
1. Elephants. I used my elephants very ineffectively, though in my defense that's because this was my first actual battle and I didn't have much idea about how good or bad my elephants were. In hindsight I would have kept them back with my Royal Regiments on the left flank, and probably sent them around in a flanking maneuever as well - or maybe kept them behind my Levy Pikemen for when the Seleucid Hetairoi charged. That way I could push back easier. Conversely, the Seleucid elephants though undoubtedly of superior quality to mine, at least managed to kill around two-hundred men before I could bring them down.
2. Loss of General. I feel that this isn't precisely my fault, though I'm sure it must have had some bearing on how the battle progressed. Statistically, King Ptolemy was probably about the 400th man to die in the battle, out of a total of 4,000. (I lost 3,000, Antiochus lost 1,000. I took a picture of the overall battle statistics screen too, that would show that, but for whatever reason it didn't save correctly). What this means is that he was killed very early in the battle. Still, how should I know that his unit of 90 bodyguards, charging into 'Very Tired' Hetaiori who have the same stats, and have been fighting their way through a wall of spears, would lose the battle. I think that part of it may just have been sheer, ridiculously bad luck that Ptolemy managed to get himself killed in a situation where 9 times out of 10 the general would be fine.
3. Hard difficulty. In all of my games playing Rome: Total War and its mods, I never played on Hard Battlefield difficulty, but decided I would do so because the RS team asks that you play H/H when beta testing. Obviously this must have had some effect, both because of the enemies' morale (and other bonuses) as well as my lack of experience playing on said difficulty.
4. Poor performance of Pikemen? I've come to the conclusion that Pikemen units appear to be underpowered. In this context, the Seleucids were able to punch not one, but two holes in my Phalanx with their heavy cavalry, taking minimal losses to said cavalry each time. This doesn't seem reasonable. Granted, the Hetairoi punched through Levy Pikemen, but a wall of spears is a wall of spears no matter how you slice it. Hetairoi shouldn't be able to out-and-out win in a full front, unassisted charge against any Pikemen unit, no matter the quality as long as they haven't been disrupted by missile fire, or some other effect (as was the case here). Antiochus with his cataphract bodyguard attacked the Kleurochoi Phalangitai though, which are a cut above the Levies but suffered the same fate, though they were completely slaughtered because they after Antiochus so generously broke their formation as if he were at the head of a Panzer column rather than a cavalry charge, they were met by Seleucid infantry. The relatively poor showing of my two Royal Regiments on my left flank in not being able to rout the Sparabara, as well as the very low casualties inflicted by my regular pike regiments seems to support this conclusion that Pikemen simply aren't as lethal or durable as they should be. I will mention again, in support of my first post, that I once more noticed that the pikemen seem to take too many arrow casualties when shot even before battle is joined, when they're at the ready and in phalanx formation. (Perhaps the fact that my Cretan archers performed so well compared to the rest of my army would support that?) Ultimately some of this poor performance should be attributed to playing battles on Hard, so perhaps I'll replay the battle on medium-difficult as an experiment.
In conclusion: I feel that either Pikemen are underpowered or the Ptolemaic unit roster is simply gimped (A problem shared in Europa Barbarorum by the way), where its Royal Guard doesn't have much bite and its Royal Pikemen aren't anything to write home about either. The latter conclusion is supported by the fact that my Royal Guard only managed to inflict 43 casualties on low-quality Seleucid units despite having stuck around for 95% of the battle, whereas my regular Pikemen routed early-to-mid battle which might at least in part account for their startlingly low casualty inflictions.
I also feel that, while Pikemen may be underpowered, the heavy cavalry of the Seleucids at least (and probably a few others) is overpowered. Evidenced by the fact that both Hetaioroi and Cataphracts were able to charge head-long into a phalanx line and completely disrupt the line while taking few casualties (and killing a King, and routing his bodyguard and the accompanying additional unit of Hetairoi that I had), while my elephants, who used the exact same strategy, were killed in very short order and inflicted virtually no damage of their own.
In the end, I am willing to admit that the AI just kicked my ass (which is not something that happens too often). Certainly on the strategic map they managed to out-maneuver me and gain a big advantage which in the end they didn't need, though that was my own strategic machinations backfiring when Ptolemy took a stupid route of retreat from besieging the Southern Wall of Jersualem to ending up North East of the city, the worst possible direction and beyond my control. And on the Battle map Antiochus obtained a very sound victory against me. That said, before anyone says 'Yes! That's exactly what we want, the AI to be able to give the player a run for their money!' I don't feel 'bested' so much as I feel 'cheated'. My soldiers performed horribly but were conducted with at least mediocre tactics. It felt like I was a ten year old kid being crushed by a high school bully, so in the end I don't come away with a good feeling about the computer having beat me, I just feel like I was expected to fight them with both hands tied behind my back which is not the feeling I'd want to give if I were the one creating the mod rather than just testing it.
Anyways, comments or reviews are welcome. Depending on what is said I might restart my campaign on Hard/Medium - Campaign/Battles to see if the results are more to my liking. Either way I'm sure I'll be restarting my campaign though, and count this first embarrassing attempt as a 'practice run' before the real thing.