Hmmmm I never did like Attached Thumbnails.
For taking screenshots and posting them into subsim I do it this way, in the game I press Ctrl+F11 and when I exit the game I move the screenshot to the desktop as its much easier to work on the image there.
After I've edited the said image its time to post it, I use this site
http://tinypic.com/, as you don't need to register with it, select Browse and find the image you want to post, select Upload Now, you'll be given 2 words on the next screen just type it in, you can use lowercase letters if you want to.
When done Select Upload Now and copy the link thats under IMG Code for Forums & Message Boards, copy that link into your post on subsim and lo and behold you'll see an image thats not an Attached Thumbnail, its much easier viewing your images in my opinion.
That's another post I won't have to write again as I'll direct every person who asks how to post images to this one.
