Question? help pls?

me and my cousin is a huge pokemon fan.. but my cousin don't have a ds.. im just thinking if i can put two pokemon platinum rom in my r4 so he and i can play with separate save files? or it will damage my r4?

no, it will not damage ur R4. I have done it plently of times! Enjoy ur POKEMON!

It won't damage your R4.
But you'll have to rename the ROM so they don't overwrite eachother.

so i just nid to change the rom name to something else? oh i see.. thanks guys

I recommend keeping another copy of Platinum called "platinumcousin" or whatever.