So to add an image onto the billboard, I select it in the actual billboard menu first then go into the Walls, Buildings, and Roofs menu to get the MGPCURVED billboard. It previews perfectly fine, indicating that when I actually place it it'll show the image. Instead, when I place it, it shows the default "FRONTIER" logo and not the image I want. I tried both with a still image and a video and nothing has been working. Help?

Billboards are like the path signs in the game.

You first place the billboard where you want it.

Then select the billboard object and edit it.

So to add an image onto the billboard, I select it in the actual billboard menu first then go into the Walls, Buildings, and Roofs menu to get the MGPCURVED billboard. It previews perfectly fine, indicating that when I actually place it it'll show the image. Instead, when I place it, it shows the default "FRONTIER" logo and not the image I want. I tried both with a still image and a video and nothing has been working. Help?

This thread may help you a little more...I think images need to be jpeg files as well.
http://forums.rctgo.com/thread-19483.html

I figured it out now. Thanks guys.