Here is conception of the DS Proto from wookieepedia
and here is the one from the movie
They look the same to me.
I also find it odd that the construction seems to be done differently than the DS 2, where they seem to be working on a level by level basis and in a north west direction. Whereas the alleged first DS they put a shell around it first then worked inward. If anyone understand what I'm saying.
Second DS Construction photo
