Yes. Renderosity's servers will not accept all file types, but certain ones they will, like .jpg, and .gif AND .txt. So, change "Radial Gradient.car" to "Radial Gradient.txt". Then Renderosity's servers will accept the file type and you can updload it to the site as a link in your message. Then whoever wants to download the file can and then change it back to "Radial Gradient.car" and it will work.