First of all, try to include at least 1 picture of your castle in the description page. Otherwise, many people won't look at it and won't download it. These people also can't comment and give you tips for improving, when there is no picture included.
Before I begin with the "criticism", let me say that I do NOT want to offend you or similar, I just want to help you getting better in castle design and thus list all the mistakes I notice. The more (possible) mistakes you know, the more you can avoid in the future (or, in this castle, correct them and update your file).
Then, on the castle design: You used too many killing pits (almost 300 of them!!) and Wazir will never build them all. Moreover, as each killing pit counts as 1 building, having a lot of killing pits included in castles can cause reaching the max building limit, if a lot of players (e.g. 6-8) are on the map. And, apart from reducing their amount, you should rethink their placement - some (single) killing pits outside the castle (especially in front of fire ballistae) can make any attack harder and (especially some human players) might find it tougher, as they always have to watch out for these spiky traps whenever they approach :D (computer enemies also, but these won't care...)
At this point one think you should always do when creating own maps/aivs: Playtesting! It helps you finding mistakes/weaknesses and is strongly recommended. And especially the problem of too less hovels, or too many hovels can be solved by checking how many he needs.
Next, there is no pitch at all - one of Wazir's normal defending measures is taken away here, making him more vulnerable.
The moat is also a bit thin - one row can quickly be dug up by any enemy, allowing them to attack the wall. So, I suggest making the moat at least 2 or 3 tiles thick. The large pieces of moat in the 4 corners make me wonder a bit - they seem a bit useless to me.
The overall shape reminds me more of a Wolf (several layers of rectangle walls/towers) than of a Wazir, to be honest, but ok... not Wazir's style, not really creative, but ok.
Moreover, you gave Wazir good things - not usual for him, but ok, it could strengthen him. However, you only placed 16 good things, which is way to few (you placed 10 hovels, so the population will be 10x8 +10 (keep population) = 90)!
And you left a lot of free space inside the castle - fill it! A bigger industry can't be wrong and unused space is lost space.
You placed the hovels close to keep and stockpile, but all the bakeries far away - that's quite unproductive, weakening Wazir a lot (especially with positive fear factor!). By the way I think a 3rd mill could make sense...
And you placed 6 stockpiles! That's too much, 3-4 stockpiles are enough for everyone.
And you placed no single well or waterpots, so when Wazir's castle starts burning, it will continue to burn until he runs out of gold. Place several wells/waterpots, at least one next to the campfire, and some "spread out" in the castle, to avoid too long ways for them when getting out fires.
If you have still some unused space, try placing an armoury and some poleturners - he will buy wood and sell spears, making some good profit.
I see you used high and low walls - but this is useless in the way you've done it. The only use of high-low wall combination is to avoid assassin or siege tower attacks. But as everyone can walk from the (outer) high wall onto any tower/gatehouse and from these onto the (inner) low wall, it is useless. You have to separate the two.
But one thing you really have to improve is your building order: The granary is built far, far too late, at building step 134, after all walls and towers and gates etc. are built. He may even die without granary, as having no granary is one of the worst things that can happen to a bread-producing ai: No profits from selling food, and no food to eat --> popularity falls down! Especially in the beginning of a game, when they have bought some wood and stone and have run out of gold, this can mean huge troubles! Moreover, low popularity means no peasants --> no workers and no soldiers.
Also the inner towers are built too late. First build the inner castle layer with walls and towers, then start the next layer. Also the bakeries are placed too late.
Same are the hovels - without them, your ai can't get peasants anyway! One tip: Place all hovels very early, because they will only be built when the ai needs them. But if they are placed late, he can't build them early, if he needs them.
The engineers guild is also placed a bit late, but that's not that a big problem... but you also placed no fire ballistae - weakening Wazir's defenses a lot.
Furthermore, there are no apothecaries, well, not really troublesome, but a usual "feature" of the Wazir.
But back to the unit placement... even if there are 5 spots each for mangonels, ballistae, fire ballistae and trebuchets, only the spots 1-3 will be set - so your bal4 and mang4 spot won't be set. You should move these spots to the back of the castle, as the back of the castle ("bottom" in the aiv editor) will always face the direction of the map edge, the front ("top" in aiv editor) will face the middle of the map, from where most enemies will approach the castle. And you placed assassins and slingers - but Wazir doesn't use these units, so these troop spots are useless. For some other troops (slaves, arabian swordsmen) you placed troops spots on the campfire - not a good idea: In case the castle starts burning, they'll all die. And, as on the keep there are two fire throwers, it is quite likely that the campfire is under fire when Wazir's keep is attacked (but, of course, some "fire-units" on the keep are always a good idea). Also note that most ai won't correctly man some of their melee troop spots anyways.
So, what else...
Maybe you could place the moat in less steps? Won't make MUCH of a difference, but it'll tidy up the setup process and principally shorten the process a bit. Placing moat early would be a good idea, as then Wazir can start digging it out earlier.
Oh and usually Wazir has an oil smelter and oil engineers placed on his walls/towers/keep to improve his defenses. Add these, you have the space to do so!
Last but not least, you placed no stairs, which means that when all gates are closed, Wazir can't access his own walls anymore and can't send new archers there. But might be quite unimportant, as the castle has two layers with each 4 gates (one each into all four directions), so probably there are never all of them closed.
And maybe you could add some dog cages? I think that would fit to Wazir and these dogs can be quite deadly for hostile archers sometimes...
Sounds like a lot of mistakes/weaknesses probably, but let me say there are also positive aspects and I'm sure you can do even better next time!
I like e.g. your high crenelated walls which are 2 tiles thick and thus assassin- and siege-tower-proof. You also placed crenelated walls in front of the towers, as they are 1. much cheaper to repair and 2. ai WILL repair walls, while they don't repair their towers and thus often lose all their ranged units when the towers crumble. But it would be better to also place 2 rows of crenelated walls here, as sometimes 1-layer-crenelated walls even in front of towers are accessible for assassins/siege towers!
Then, you made a two layered castle with quite well-placed towers, from there Wazir's archers can shoot anywhere (no blind spots). By placing wall in front of the towers you also make one attack-strategy impossible: Just attacking one tower with a bunch of macemen and running through the gap towards the keep - with additional walls they won't survive long enough.
And, you tried to use high-low-wall combinations, even if you did it not so well.
And, in front of the bakeries (with a 1 tile gap for walking) you placed high crenel, which may hold off some fire ballistae burning spears of and thus makes the castle harder to set aflame.
So, I hope I was able to help you.
[Edited on 07/21/11 @ 06:48 PM]