If you've added your pics to this site's picture gallery, and you've figured out how to get one of those pics to display in your post, then simply copy and paste that reference (includeing the begging and ending html tags) and just edit the picture ID numbers to match those you are trying to display.

Or, click the 'image' button provided to the right of the smiley faces and add the pic referecence location. You can do this as many times as needed...

There may be some limitations depending on you OS or browser version though...