Supercard mini sd double white screen HELP!?

Whenever i try to put a nds rom onto my supercard mini sd, it loads up and then comes up with 2 white screens. I have a supercard mini sd,super key and i know it can work as i have put gameboy advance games on succesfully. I have changed the .nds files to .nds.dsq and .sav through the supercard software but it still doesn't work! Does anyone know why this is happening?