I've seen the same thing. In order to get the BI studio to publish my project. I had to remove the <Description></Description> elements from the .cube file manually.
>
> Has anyone ever received this message before?
> "The Description element at line 3123, column 29 (namespace
>
http://schemas.microsoft.com/analysisservices/2003/engine) cannot appear
> under
> Envelope/Body/Execute/Command/Batch/Alter/ObjectDefinition/Database/Cubes/Cube/Dimensions/Dimension."
>
> All I was doing was adding description to the properties of the dimension
> tables. I was doing this so that the report user can see pop-up descriptions
> in Report Builder.
>
> I haven't been able to resolve this problem. Not only that - Now that I've
> received this error, I haven't been able to reset the solution file so that I
> don't get this error. I have even removed all the description changes I
> made, but to no avail.
>
> Can anyone help me?
>
> --JP