Here's how to include a photo in a new place, comment, or forum post.
I'm assuming your photo is hosted on another server, and you know the url of the file, eg
http://byfiles.storage.live.com/y1prhjovjDKlK7f4ROWXz3x-URBoPSLzpGbDli3L8mBQ0ntZ0gePDldxEf_QqyVCOGx
If we take a new comment as an example, you'll need to paste a small piece of HTML in the comment you are typing. Don't worry, it's just a simple cut & paste of the following text:
<img src="YOUR URL HERE" alt="" />
So for the above example we'd use
<img src="http://byfiles.storage.live.com/y1prhjovjDKlK7f4ROWXz3x-URBoPSLzpGbDli3…" alt="" />
Before you paste, click the 'disable rich-text' link under the edit box. That puts you into 'edit html mode'. After the paste you can click the 'enable rich-text' link to switch back to the normal editing mode, and you should see the photo displayed.
MrB