Washing an h.NAOTO purse?

EDIT So far, I've scrubbed at this purse, and I've gotten most of the dirt off, and the print is still firmly in place. C: I'm using cold water, a hand knitted cotton washcloth and Mrs. Meyers detergent (It's an all natural detergent that I got from Kroger's, if you live where there are any) and so far, it looks good. No fading or running! 

Wooh, first post to egl and all! I'm Tora, new to wearing lolita, I've done a lot of research, I've been into visual-kei for a while, I'm wearing my first actual lolita coordinate this weekend, and I need help! D:

So I have an h.NAOTO purse, I've had it for a little over half a year, and.. well, it's a little dirty in places.

This is the purse I'm talking about


Is it ok to spot clean it with cold water and a mild detergent, or is h.NAOTO one of those brands that has a print that runs away if you get it wet at all? I'd rather my purse be a little bit dirty than let the print run everywhere. x: