Crash When Adding New Decal Road

I was making a replica of Mt. Nebo Arkansas, and then suddenly I can't add anymore decal roads. Every time I add one it instantly crashes as soon as I click.

I need to add more roads. I don't believe I went over the road limit? I only have 19 roads in the scene.
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Ok, I think i know what's causing the Torque Engine to crash. The WarningMaterial material. I placed a regular decal that used the default WarningMaterial and guess what? It crashed too.

Now I know it's the WarningMaterial, but how to I fix it? I don't understand why the heck it is causing a crash! I need help, I cannot continue working on my map until this issue is resolved.