lolflakes,
1. Make sure you keep trying to "fully load" the "External" package (in the generic browser, left panel, under "Packages"). You really need to do it 3-4 times. Do it until "fully load" is greyed-out. After this, make sure "External" is still highlighted and look at the filter window that is located in the upper-middle of the generic browser. Look for "Object Type" highlighted in RED. Check the "Materials" box. All of the games "Materials" should now show. They will not have thumbnails but you can still use them as normal.
2. Since you can't see the thumbnails, you won't know what anything looks like but you can look all of these items up in each of their individual package folders. To see landscape textures, for example, go back to the filter window and click "All". Then click "External" in the "Packages" window. Now, look in your "Packages" window for the folder called "ENV_Landscape". Click it and now you should see all of the textures in that package. Write down the exact name of something you like. Re-select "External" and then go back to the filter window and select "Materials" Look up the name (it's alphabetical, not everything is there, though) and then click it. Now you can go back to your Terrain editor (the little button that looks like a mountain) and add it to your terrain.
