Sometimes supporting files are not where they need to be.
If you use DITA2Go to generate OmniHelp, then when you load _myproj.htm the browser displays only this message, and nothing else happens:
This usually means the OmniHelp viewer files or control files are not in the same directory as the HTML files; see §19.2 Setting up OmniHelp viewer control files.
Everything where it belongs? Next: Check the DITA2Go User’s Guide.