I created a number of emails using the email template "EM - Noble V1" and I have campaigns actively using these emails. Without notice, spacer images in the template (hosted on dropbox) are no longer accessible, which has wreaked havoc on the emails.
Unless there's a quick fix for this, I'm going to have to rebuild these emails in another template. I might avoid other templates altogether if this is a risk across the board with the supplied templates!