Above, Galdámez Acevedo is correct. Galdámez is the surname of his father. Acevedo is the surname of his mother. In everyday life, he was known as Señor Galdámez or Abuelito (grandpa) Galdámez. He signed his name as Guillermo Galdámez A. But he never signed it as Acevedo. None of the Latin American men I ever knew or still know use their second surname, only the first surname. Even though legally, both names identify the individual.
The Latin Americans nearly always use the name of the father, if known. Otherwise, the child has only one surname, which is the surname of the mother.
However, below, José Acevedo () is not a name by which neither he nor anyone else ever addressed him. Both names refer to the same person and both are labeled "her father", but it is easy to become confused, that maybe they are two different persons.
So whether the names be shown as Galdámez/Acevedo or Galdámez-Acevedo or Galdámez Acevedo, both names boxed or in italics or bolded or whatever, maybe someone can figure out how to show both names as surnames, like the the old now outdated, antique and ancient PAF used to include both names in a surname box.
If I don't oversee something, You cannot configure this naming convention.
By the way, with the FTB it's possible to configure this latin naming conventions, it's called Use Spanish tradition for suggesting last names of children.
But it's complicated to handle properly to use this option, if You have a 'mixed tree' with latin persons and others.
I'm using on our online familytree the option to add a former name. In the main person fields I'm entering the name like it occurs on official documents (births certificates, etc.). If I take Your sample:
Firstname: José Guillermo
Lastname: Galdámez Acevedo
Former name/Alternative name: José Guillermo Galdámez, Abuelito Galdámez, ...