I am creating an email template inside Adobe Campaign Standard which has some images. I would like to personalize the URL of the the image in the src attribute. I have created a custom resource inside ACS which contains a list of movie names and their corresponding poster image URLs. I would like to have this poster image shown in the image element of my email page. I have tried enabling personalization in email designer page for my image element and tried including the poster image URL field from my custom resource in the personalization field but that doesn't seem to work. We do not intend to use Adobe Target.