What might be wrong when this happens: I export a mesh from the sims 3 in CTU ---> Import it into milkshape by GEOM importer ---> it says unable to locate bone file, default skeleton used and then the mesh looks like it totally exploded.

I had that same problem a while back, see this thread here: http://www.modthesims.info/showthre...012#post2790012

Read from post #21 (my post) onward.

Now it works but it still makes me use the default skeleton, is that all normal? Anyhow could you tell me what did WesHowe mean by this:
"What was missing was the matching .skcon for your mesh, it should be extracted also, when it is present, the plugin resets the joint positions to the exact values in the file."

Am I supposed to extract some .skcon file? Sorry I'm still such a noob with this since I am yet learning mesh creation.

Using the default skeleton is fine for most things. If you have problems, then you can try extracting the .skcon file from FullBuild0.package, but you shouldn't need to.

alright then, thank you

This is correct. The big caveat is that the default is an adult (good for teens, too). It fails on children and toddlers (doesn't crash or anything, but a child mesh only gets up to about the spine1 joint).