Alrighty, I had some free time this morning to test advmame. Finhead, thanks for making me take apart my working config, JK. :p
Ok, here's the deal. Like Nitro has already pointed out, advmame is awfully slow running out of x. The reason is advmame and some other emulators in emulationstation are configured to run on framebuffer. Thank god for retroarch, right?
Anyway, to get advmame to launch from attract you need to edit this /opt/retropie/configs/mame-advmame/advmame-1.4.rc file and change at least these two lines. This will stop the video and keyboard errors.
To this...
device_keyboard auto // which was set to raw
device_video auto // which was set to fb
Here is the emulator config I used.
executable /opt/retropie/emulators/advmame/1.4/bin/./advmame
args "[name]"
rompath /home/pi/RetroPie/roms/mame-advmame
That said, all this is really pointless because the games are barely playable. But, but.. we might be able to get around this by creating a script to close am then exec advmame and on exit have it run attract again.
What do you think Nitro?