Trying to filter group user members by username and the UsernameFilter doesn't seem to be working...
#set($options ="%{GroupId = $core_v2_group.Current.Id, MembershipType = 'Member', PageIndex = $cPage, PageSize = 25, UsernameFilter='lukedavidson'}")
expected result is to get user with username "lukedavidson"
result is all members are returned as though the param does not exist.