I've been testing Wysija and I want to love it and go pro, but we just can't get consistent results out of the receipt format of the Preview emails (whether it's the default template or another). When emails are received by some recipients (independent of email client) the emails go through fine, on some others (like gmail and even the domain that is hosting the wordpress site) the emails just appear completely blank.
I'm taking a wild guess when I say that I think it has something to do with the way the mulit-part mime is set out and being interpretted???. Even on the emails that "look" blank, the source code is there. But the code between the multi-part mime delimiters is completely different between the emails you can see and the ones you can't.
I can't figure out what's going wrong.
It doesn't appear to be a simple theme plugin conflict (switching themes gets same results).