All the pages I have tried are published in all the languages that exist on the website.
Is it possible for your server to resolve the URL you are connecting to? What I mean is if you are browsing http://www.address-to-your-site.com from your server, will the server be able to reach the site?
Make sure that your siteUrl-setting in Web.config/EPiServer.config is correct. I had problems with EPiServer Mail preview/sending when using an alternative hostname different from the one defined in siteUrl.
Whenever I select a EPiServer CMS page for my HTML content it says 'No HTML content' found on the Preview/Send page, and displays a little red star next to the Browse button when I switch back to the HTML-content page. Anyone else experienced this? Creating my own HTML content or fetching an external URL seems to work flawlessly.
I'm using CMS 5 and the latest version of EPiServer Mail (4.3.0).