Well, I ended up installing a script that rolled back all the campaign dates to start in 666 and that seems to have gotten around the time limits. I ended up playing about 100 years starting as the Irish Duchy of Munster and had a blast. It took me a few years, but my second ruler, who lived to the ripe old age of 78, managed to unite Ireland and declare himself king.
I really like the way claims work now, and it makes the strategic use of manufacturing claims a lot of fun. In particular if you hold at least half of the counties in a Duchy you can claim or usurp the Dukedom. Then once you have the Ducal title you can make a ducal claim on any counties that aren't your vassals already. As a result I was able to take over a lot of Ireland just by making a claim on one county, taking it over, and then using that to usurp the ducal title.
So in Ireland I was able to almost immediately take Desmond as it was in the Duchy of Munster, then after a few years I was able to get claim on the counties of Leinster and Dublin which, after a couple wars, gave me control of the Duchies of Leinster and Meath. That gave me control of over half of Ireland which let me take the title of King, then I was able to make vassals out of the rest of the independent counties in Ireland. Of course once I had Ireland under my control most of Northern Ireland slowly rebelled over the course of a few years, but that let me put some of my King's many sons on Ducal thrones throughout Ireland (he had many sons thanks mostly to a lusty little Byzantine Princess who had something in the neighborhood of +40% to fertility
Unfortunately, while the first king of Ireland was loved by all, his idiot grandson and heir was not so well liked. Worse yet his idiot grandson had become heir only after his father died under mysterious circumstances during a hunt. So when King Brian the First of Ireland died while leading a campaign to claim part of Wales for the Irish throne, his grandson finally came to power and nearly all his new vassals began to think of rising up. Thankfully they did so very piecemeal and, while the constant wars lasted for 10 years or so, the new King was able to use mercenaries to bolster his forces and eventually subjugate his unruly vassals.
The idiot grandson did finally go on be a rather good king, even if some of his vassals might disagree after spending some time in his dungeon contemplating their mistakes.
I finally stopped playing when King Erin died and *his* idiot son took the throne which once again destabilized all of Ireland (and by that point Wales which had slowly been taken over by Erin the First.
And even worse... the thrice cursed Duke of Brittany somehow got a claim on one of my provinces in Ireland and launched a war to reclaim "his" land. I learned the hard way that apparently galley's can't fight, so he was able to land his sizable army on Irish soil and take control of that province. The sad truth is he was only a Duke and had fewer provinces that I, but they were wealthy and prosperous compared to my poor lands so the levies from his smallest province were larger than the levies I could field from my capital. I would have needed the support of 2 mercenary companies to fight him, but I just didn't have the money I needed at that point to succeed.
The rest of the map was pretty interesting to look at by the end as well... the reconquista went poorly in Spain with all the Spanish Kingdoms except for Aragon getting taken over the Caliphates. Aragon however had merged with rebel Aquitaine in France and had become a powerhouse unto itself. Where the Spanish has fallen the French and the Holy Roman Empire were fighting the Muslim's in Spain now with some success, but the HRE was beginning to fracture under it's own weight with many provinces rebelling during one of the transitions of power.
Byzantium was going rather well having held off the Turks and other Muslim factions and they had even fought well into modern Iraq and Syria before being slowed down by a change of power and the unrest that followed. Meanwhile farther north, Poland and Denmark merged for a short time under the King of Poland until Denmark fractured with rebellion (led by the Duchess of Skane and her husband, a dashing Irish Prince of my lineage).
Anyway, the game is great fun and is an improvement on CK I in almost every way. The first CK was fun in spite of it's interface and some of the more broken features, but CK II is a dream to play by comparison, and the stories that come out of it are at least as rich as the ones from CK I.
Can't wait until next week when I can give the full game a try.