Nintendo DS Lite and MK3

Just received my MK3 and neoflash 1GB cart in the mail today for my ds lite. I am a little stumped on how i can get roms and homebrew software to work though. I installed the NEO_MK2_3_Menu_V0.4a onto my gba flash cart from the slim loader 3 placed the cart into the ds along with the mk3 and new mario brothers game. When i fire up my ds lite i just get two white screens.

Is there a tutorial on how to get ds lite to work with mk3 and gba flash cart. Or can someone let me in on how to do this.

Thanks

Im having the same problem but i can run backups of the GBA on the DS lite but cant save the GBA game? also how do i run DS backups using my MK3 and the NEOflash 512???