That got me going. I set up the project on a network share which could be accessed from my windows machine and a mac. Then I used a different editor (Sublime), as opposed to Visual Studio and notepad. The UTF-8 files created by Hugo worked fine in both environments. The issue was the UTF-8 encoding used by notepad and Visual Studio was UTF-8 with BOM, and that is what was causing the error:
ERROR: 2015/06/15 Error parsing config: Near line 0 (last key parsed ''): Bare keys cannot contain '\ufeff'.
The encoding I needed in Visual Studio was Unicode (UTF-8 without signature) - Codepage 65001