are you putting the XML in the client as well, or if you are putting it in the client, are you putting it in the server as well? Needs to be in both, and one side not having the xml would definitely cause this. I know its a stupid question of me to ask you because from the looks of it it seems like you've added custom items so I am sure you would be familiar with implementing XMLs.
Make sure you have written the XML 100% functional as well (even tho XML errors wont let you get past loading the server xD but you might have forgotten a tag or added a tag that isn't supposed to be there, etc), take a look at another enemies XML, like a dungeon boss such as Septavius or something, and base it off of that.
You can also try debugging wServer app to bring code errors to your attention :P