seta r_customwidth "1600"
seta r_customheight "1200"
I changed these to 1024x768 as that's the highest my cheap TFT can take.
Unfortunately it still isn't working and defaults to 640x480 according to the terminal output. I'm not really confident enough to mess about with xorg.conf as I've broken stuff before doing that!
I'll see if I can get it working in a window...
edit: hmmm.... in a window it's enormous and I can't see the right hand side of the window. Also, the sound is a bit funny but I'll worry about that later. This is all a bit confusing...