Welcome Back Regions ?

Well Im about to download my two free games. but Im worried about 1 thing.

you see I had LBP Disc but now its scratched! Im going to download LBP Free Game. but my question is.

If I download it from US store and my save files were EURO would I lose them? would the EURO add-ons work on a US LBP?

and also Im going to download DEADNATION. Can I play with my friend that has the US one if I have the EURO one?

THANKS SO MUCH :D !!!

Add-ons are region locked, If you can just download the add-ons on the US region it's prolly free by now.

and as far as save games are concerned i'm not sure.