Devi- Thanks for replying!
While I didn't copy and paste the sections I think you may be on the right track. Since a lot of the sections contained some of the same fields I was just referencing them from other sections so that, for example, I could set all cost fields to be doubles in one go.
May be that had something to do with it.
Another wierd thing is that when I export it to work without the service pack it works fine! Because of this, the situation has turned into a curiosity rather than a problem.
thanks again anyway.