Got list of age grouping from SD at my request. (<14, 15-19, 20-24, 25-29, 30-34, 35-9, 40-9, 50-9, 60+) They will be used in the visualization tool which currently gives every possible age a different colour value (so it's pretty well useless).
Simplest approach seems to be to add an age_group element to the XML which contains what amounts to the foreign-key-lookup value for the sql table. Then read that as a field into the criminals sql table. Add an age_groups table which relates the integer foreign-key value with the text value to display to the user. Done all that to the dev and production sites.

Next I have to modify the import code to include that age_group_id value (and a couple of other values we've added like corpse_treatment). Once I've got the database populating correctly, then add the code that queries and reports from the db to make use of that information in the visualization. Started that on dev site.