I was trying to figure this out and found the following code works great for adding more images to content without using the "add image" link in the editor. It requires you to look at your section in "Source" mode (HTML code view) and place the following code where you would like your image as well as a link for the image. It's obviously for users with code knowledge...but it seems to work great.
<a href="http://www.your_image_link/nlimages/SP.htm" target="_blank"><img hspace="7" border="1" align="left" width="100" src="http://www.youir_image_url.com/nlimages/spthmb.jpg" alt="" />
Just a FYI
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