(Aom:EE) Is the "Campaign Maker" tab in the editor broken or nit?

As far as I've tried, I was able to string two scenarios into a campaign using the built-in Campaign Maker, but wasn't able to start the first level (immediately getting thrown back to the menu).

Is there some way to make it work, or are there any other methods? Or are there any steps I missed?

Edit: Title's supposed to say "not", instead of "nit"