Hello luke,
You can add the following code to your bp-custom.php:
add_action ('bps_field_before_search_form', 'set_defaults');
function set_defaults ($f)
{
if ($f->code == 'field_5') // drop-down field
{
$f->value = 'Canada';
}
if ($f->code == 'field_10') // location field
{
$f->value['distance'] = 5;
$f->value['units'] = 'miles';
}
}
Replace 5 and 10 with the actual IDs of your fields.