1. I'm pretty sure you'll need a script for that. Just look around for a message system script or something. I looked around here real quick but didn't find one offhand, I'm sure there is one though.
2.
\C[n] Colors text from that point in the color numbered n. What color n represents is set via the system graphics.
Quoted from the help file in RMVX.
Don't worry, I forget to check there too.