Well, following on from my in-progress posts...after taking out Monty's cap fairly late compared to most here (the only civ I actually used Keshiks as my main invaders for), and the successful naval invasion of Moscow, and then march to and capture of Athens, I turned my attention to the other continent. As soon as I was able to upgrade to infantry (bulbed the tech), my troops set sail for the other continent. We landed and took Rome without losing a unit. After some turns and a GS/Oxford combo, most of these troops (now mech infantry) reembarked to sail around to attack Gao (Oda was already wiped out by Songhai).
In the meantime, a newly built army was massed to invade Siam, via the coast to the SW of his capital, squeezing between his 2nd or 3rd city and the mountains there. This was much easier than expected; I think I only lost an artillery at sea, as I had to re-declare war on Greece just to pass through his sea lanes to get all my units into place to invade en-masse.
So I took Sukhotai on the same turn my units had landed against Gao on the other continent.
This is where it all went to hell. Siam's cap was size 34; so as a puppet it added 17 unhappiness, which took me well into the red (-33% combat penalty, etc). Oh and somewhere along the way Russia, who'd been building units galore (they hadn't used many against Greece; I'd gotten Siam and Russia to declare on Greece to try to whittle down their armies, but Greece was already too weak to do much)...Russia retook Moscow, which only had a mech inf and an artillery as token defense.
With the combat penalty, and Songhai also having built Himeji, the Great Wall, and the Kremlin, my mech inf were taken out by cavs and infantry. A few units retreated back to sea.
To really top it off, Russia came looking for peace not long after re-taking Moscow. Somehow (it was late, I should've been in bed, thinking was not clear) I imagined I'd solve my happiness problems by gifting Russia Athens (they were offering even peace). I'd completely forgotten I'd recently annexed Athens and bought a courthouse there. It also had Chichen Itza and the Taj too. So instead of improving things, this disastrous idea meant my happiness went from bad (about -14?) to much worse, -23.
I couldn't believe I'd screwed that up so royally. The initial happiness issues on taking Sukhotai were difficult, but would've been solvable. This was too much. Oh, and by this time no one would give me open borders, so my army at Siam was almost completely boxed in; it could only exit to the northeast, through a city state, which meant using it again on Moscow would've been a very long path. Before I shut down I'd decided, well , I'll just have to retake Athens, and had marched that army toward the outlet....
I doubt I'll load it up again though. My infrastructure is seriously compromised (only one or two public schools, one factory) from building units for so long. I've only come close to rivalling Askia's army at my peak military, and he's got nearly double production, nearly the entire other continent. Rome was holding him off before I arrived. Russia, and possibly Siam, might still give me trouble. And the happiness issues are quite a knot to unravel.
It was a fun game, though I took much too slow an approach. I built five cities to start. Although I think this was what allowed me to have a tech lead for most of the game.
Before hitting the happiness wall, it seemed like the game was in the bag, and even Gao would fall to mech inf and artillery pretty easily. Funny to see such a big reversal. It might be a salvageable situation...then again, it might not. Ah well. Next!
oh and please someone confirm for me that you can't buy a courthouse until the conquest disorder is finished--17 turns!
In the end I had to load a dozen fighters onto 4 aircraft carriers and bombard Rome from 12 tiles away. I floated all the crappy units that Almaty had given me across the channel, and one eventually made it through to take the battered city. 
