Oy, my desktop is always in 32 bit, on my Athlon 1.2ghz at least.
I've tried with new combine/tv aspect on and off, tried with sound on and dummy mode (though its a "Video Plugin Error" so I'm assuming its not sound).
Sometimes GoodN64 mis-thinks that roms are good when there is something wrong in them, I'm assuming thats what it is since I tested it on such varied systems. Btw, cool screenshots, as always =)