To make a grouping in a Surface file:
Groupings can be manipulated by either the (very slow) Show command which removes all other elements and displays only the Group, the Add/Remove commands which do what you might expect, and the Nop option which does no operation. Groups are easily renamed just be altering the name in the text field. The order is harder to change - one must redefine the groups from start to finish by selecting the group, creating a new group from it and then deleting the old one. There may be a more elegant solution.
Groupings are saved as part of the .surf file