The ASCX for getting the first URL alias for each child in a repeater list is
<%# CMS.DocumentEngine.DocumentAliasInfoProvider.GetDocumentAliases().WhereEquals("AliasNodeID", Eval("NodeID")).First().AliasURLPath %>
@Trevor, I tried that macro {% Documents[NodeAliasPath].Aliases[0].AliasURLPath |(identity)GlobalAdministrator%}
before and it doesn't exist