Playing my second game. I've got the Immortality Mod active and I've got a few questions.
Currently a Count. What are my routes to becoming a Duke?
You have conquest - through claim-fabricating or a holy war - or marriage - marrying a relative of a duke such as his sister or a daughter, providing they have inheritable claims and are not 45+.
I tried forging a claim a couple of times. I currently have a strong claim on Zagreb, but I can't go to war with them because they're not independant? Am I limited to waiting for a lord to declare themselves independant and then sending my chancellor to forge a claim there?
Whenever you declare war, you have to declare war on someone who is either independent or has the same liege as you (eg. Duke of York can attack the Duke of Somerset, but the Holy Roman Emperor cannot attack either of them. He would have to declare war on the King of England if he had, say, a personal claim on the duchy of York.) If it's displaying something like
Code:
([color=red]X[/color]) Count Whoever of Zagreb is not independent
then you have to declare war on his liege for Zagreb. Presumably that would be the king of Croatia.
How long do claims last? My claim on Zagreb is still good, even though it was forged years ago. Is it worth to try to forge claims in as many nearby territories as possible on the chance I could make a claim?
Claims last until you die. Forged ones won't be passed on to your offspring, and they don't expire without a character dying.