Relationship imports can be setup for Resource objects in GAL.
Item1Id|Item2Id|ItemRelationshipType|Notes|Description
Item1Id:The ID of the first item. Must match ID of item in Global AlertLink
Item2Id:The ID of the second item. Must match ID of item in Global AlertLink
ItemRelationshipType: The name of the referential data item that represents the type of relationship to create
Notes: a notes field for the relationship
Description: a description field for the relationship
We could set up an import using onlyItem1Id|Item2Id|ItemRelationshipType. They are required (and ItemRelationshipType could certainly be eliminated on the map if you only had one relationship type).