OK. Final post as it would seem that Edge isn't yet fit for the task I was asking of it.
I completely remade the Edge Project so that the only files in the Library were the files which were actually being used in the project. When I published the new file the programme dragged lots of extraneous files into the Library regardless as to whether they were part of the project or not. And of course as a result the OEM file was corrupted again.
