You do this:
1)Go Advanced at a post, and scroll down the window a little, and you'll see a button with "Manage Attachments" written in it.
2)Click it (duh
), and then upload the images you want.
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About the terrain:
1)Don't worry, it's far from a disaster! You should add much more rocks between the trees, and clusters of shrubs near the rocks and the trees. That will make it look more "savage". Oh, and some birds are going to fix good too.
2)About what Oziris said, that the grass in front looks ugly is true. You should add a cluster of grass in front of the screen, a large mass of it. Some rocks could fix good, but the main thing is the grass. By adding only one grass model, you're just making it worst, then you have two choices: 1- Add lots of grass models; 2- Adding no one.
I suggest you to add them.
This is what I mean. Can you see the grass in front of the camera?? You got it then.
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I hope I helped!
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