@main: Yellow or white.

[GM-Pandora]

Here's how it works:

Oddly enough, If specify any admin in one of the files contained in your hero.grf, this admin will have GM clothes + the main will be white. If I don't specify any admin, it will be yellow.

To make it another color would require hexing the client, I have the tools to hex I use them already to tweak it. But what I don't know, is the exact string where it specifies Main Color. If I did I suppose I could change it to another color (green, purple, orange, blue, etc.).