In some projects, you might have sensitive information, such as answer content in an e-learning project. It's possible that some of this content could be seen as items on the page are being loaded, if you've used other items to block that content (and the blocking content hasn't yet loaded).

In this case, you can hide all the content by attaching some CSS.

Attach the following code as a .css file in the Resources section of the in5 dialog (how to attach resources):
#container { display:none; }
body.loaded #container { display:block; }

With this code in place, the viewer will only see your document when everything (including the blockers) are fully loaded.

You might also want to turn off Lazy Load Images in the Advanced section of the in5 dialog, as this will cause content to be progressively loaded on subsequent pages.

Alternatively, you could use either Multi-State Objects, Button (Hidden Until Triggered), or Animation properties (Hide Until Animated), to hide content in a way that does not require "blocking" content to be loaded.