Select the photograph you wish to post into the thread - note the picture ID number.

Go to the thread you wish to insert your picture in and then to the post/message box (same as this one, lol)

Type your title, description or explanation in the message area, 

then click on the green tree icon, third from the right in the tool bar below. 

A pop-up window will appear - type in the ID number of your selected picture and you should see your chosen picture appear in the pop-up, if the pic doesn't appear delete the last one or two digits of the ID number and retype them. 

When you see the pic appear in the pop up you click INSERT. 

The pop-up window will disappear and you will see your picture inserted into the message/post. 

You can now insert another picture the same way or you can click on POST and your message with the pic will be sent to the thread.

Hope that will help you to join in with all the picture chat threads now.  Have lots of fun

Great idea, this explanation. Hopely much more people will join in.

I always copy paste the picture ID. (select the number with your pointer [cursor] and copy using your right mouse button)