Divide away. Usually you'll see the runners are only attached to the parent by a single root. Grab firmly at the base, pull up until a reasonable amount of root is visible (sometimes the whole thing just comes up), pinch off and replant where desired. I actually pulled up close to 35 or 40 nice sized runners (plantlets) and sold them to my lfs for $2 a piece. Come to think of it, I can't remember a crypt relocate ever dying on me.
** note ** mine only made a mess because I have potting soil under sand. Well it was under the sand until the crypt roots made it above the sand. Even then, a quick vac and go and all is right as rain again.