You need to be in the "advanced", not "quick" reply mode or know the markup used for images if the image is already on the web somewhere. I have server space, so that is where I stash images I want to post here.
You'll see this icon in the top tool bar:
Click on it and follow the prompts.
Alternatively, you can use the markup [,IMG]url of the image[/,IMG] (without the commas)
I don't know how the other piece works though...
It says you can load the image to the forums space (but it is quite limited).
As you said, you are supposed to use the "Manage Attachments" selection
under the message entry stuff where it says "Additional Options", "Attach Files" and then follow the prompts.
It doesn't do it for me either

*
Unless* I click on the image, then cut and paste the url of it into the appropriate markup such as:
[,IMG]http://www.bladeforums.com/forums/attachment.php?attachmentid=37164&stc=1
[/,IMG]
(again, without the commas...I have to use them to make it *not* work and show the image).
I hope this helps!
WAIT A MINUTE!!! It did work...it just doesn't show up in the preview page!!! Look below and you will see the images in the thumbnail section! Yee-Haw! We gotz hot water!
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