By an amazing coincidence, Duraz Kazad is only on the other side of the mountain from your Hold. We make natural allies against the grobi who infest the region!
I'm bored, so I hope you'll forgive a short story:

That turned out a bit longer than I expected, but I enjoyed writing it which was the main thing. Consider it an alliance request to your king (or queen?). I would of went further, but I don't know enough about your Hold to want to describe it.
It was great...I really liked that story it is characterfull and is a great way to introduce Kazad-Grund and itīs halfing populance, I am quite sure these was Bloody spear halflings, they are the most warlike ones.
Ok, ok, onto what you want to hear. I really like your background, but you have to flesh out some things as well. It's a good idea, one that I've rarely seen before, and I want to know more about this! Do the halflings live underground with the dwarfs or outside the Hold? Maybe they could have their burrows, carved from stone, near the surface of the mountain, so they're reminded of their homeland?
They live underground with the dwarfs but many of them work up in the surounding farms, there has been times when they lived in the farmhouses but it is not safe.
Oh, and I remind you that before Sigmar's time, the halflings would of just had furs and stone weapons, probably. In fact, I think they were yet to come to the Old World at that time... I can't imagine them surviving long in a land plagued by Orcs. Maybe you could adjust your story a bit so it was a meagre thousand years ago or so that they came to Kazad Grund?
I know, the reason that they moved here was that they found the moot unsafe, after Sigmars time it was protected by the empire but not then, the halflings of Kazad-Grund are ofcourse more dwarflike than imperial halflings as a consequense of this.
Oh, and I loved your map. If you ever had time, would you consider drawing up a map for me? I need one for my WHFRP campaign, but I have to use Paint becaus I don't have a scanner, so you can guess what that looks like

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I can quess what it looks like and I quess itīs not pretty, I can probobly help you with maps that one was made from the one in the 6,5th edition rulebook by...something wich I donīt know the name of in english which is simply that you use almost transparent paper, places it above the thing and draws according to the pictures (which you see through). Iīll check Duraz-Kazad up if I can find youīr information and then I might even add it to one of the maps I have done (if itīs close enough)
I have written more about the hold and I will try to get all my text into the computer soon, that is the annoying part with using pen and paper, itīs harder to post at forums.