To post a link, go into Post Reply, type your message and then highlight the word or words that you want as a link. Then click the blue globe icon above and you'll get a box to paste your link into. Do that, click OK, then submit reply and your link will be up and running.
You can make that link to a photo as well, but if you want to show the photo on the site page, this is the way. To use the following you'll need to place your jpg online somewhere like Flickr.co. First make sure your photo isn't too large for the site pages, 640 x 480 at most. To add the photo to your post that's already online somewhere, go to your online photo, right click it and choose "Copy Link Location" from the context menu. If that's not in the context memory and you are using Internet Explorer, select Properties, then copy the URL from that properties page.
Then when back here and replying, place the cursor below your message or where appropriate, then click the yellow mountain scene icon above. Paste in your link from the photo, ok it, and submit the reply.
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