When a recipient receives one of your newsletters, depending on how their email software is setup, the images may not automatically display. Most email software, like Gmail, Yahoo, Outlook etc., require the recipient to click a link to "display images". This is not something controlled by Flashissue and it applies to any service you might use to create an email newsletter.
To view the images, the recipient needs to click the "Display images" link in their email software. Here's an example in Gmail: