This post is written to make clear matters of region-lock.
PlayStation 3 is region free - it doesn't mater where you bought the console, or where you buy your games, they will all be compatible. However, DLC is region-locked - for example, when you have Japanese release of game you will not be able to download DLC from your not-Asian account.
So, if you want to import JP release of Chronophantasma and you want DLC, you have to create Asian account.
I don't know if my information is 100% correct, but if something is not right, let me know it here and I'll change my post.