I had a little play today, with loading pics. onto a post.
Worked a treat.
You might have chosen a day when there were too many stray gamma rays around
Seriously, check the FAQ area if you haven't already.
I managed to link a pic. of my body rotisserie from another web site easy peasy.
I could have loaded it onto this site and done much the same thing but I didn't.
When posting, you click on the "IMG" box.
Then a "scripted window" should appear, asking you for a URL.
You then paste/type a link that goes EXACTLY to the pic. that you want to insert.
[FAQ is good help here].
P.S. If you don't see the scripted window, your PC may be not allowing it to happen.
It should alert you though, that the site is trying to open a scripted window, you then allow it to happen, then reclick on the "IMG" box and you are away.
Then it all happens