Yes, you can embed code for objects or <iframe> from third-party sites.
Copy the code from the third-party service.
ClickEmbed in the Elements tab.
ClickCode Snippet.
Paste the code that you have copied into the text box.
Click OK.
Note: In the Elements and Apps tabs, you'll find additional widgets, such asFlickr, Google+ Photos, and Video. These widgets will allow you to upload albums from your photo-sharing accounts.