Setting blank content can have some weird side effects - is that
necessary? Have you tried setting up the same campaign and generating
the text through the web interface? My guess is that between the
template and any HTML content there is some really bad markup that's
making it impossible for the text generation to happen. Other than
that, though, it's extremely difficult to troubleshoot this with this
few details about the campaign content, other options used with
campaignCreate, or seeing the campaign you've created.
If you've seen this happen via the app, have double checked the
template+content for bad errors, and still can't get anywhere, post
the signup form for one of your lists and the campaign id in question
and I'll take a look.
jesse