Yes, for years they had a rule against interracial dating. Their scriptural basis for this rule want was related to the Old Testament proscriptions against having intimate relationships with the people of other tribes and nations. Extending these restrictions to prohibit Christian students from dating another Christian who happens to have a different skin color or nationality had a pretty questionable basis, especially given the New Testament teachings of Paul and the fact that King David was the grandson of the product of an "interracial" couple.
In practical terms, the reasoning for it was more of a cultural and social basis, and at the time there were some very practical reasons why interracial dating was often a bad idea. Our culture and society has changed so much since then that the major problems an interracial couple faced then are more of an exception than the norm now.