I did a quick forum search, and it looks as though adding ElementPath might have been a mistake; in short, don’t assume that a message indicating a “missing module” is necessarily indicating that this is actually a problem.
These threads in particular seem as though they might be useful to you: 1; 2
I think that it might be better to approach this from a different perspective: First, undo the changes that you’ve made for those “missing modules”. Then rebuild the p3d file and, presuming that it completes the build, run it. We’re expecting that to crash. Once it does, look for the log file and see what that says–that, I think, is likely a better guide to where your problem lies.