That's really all there is so far, don't know if that works at all right now, and don't take this as recommended way, I just looked in api-doc for procs that do what I need:

ReturnHeaders

apm_ns_write_callback "Installing packages

"

foreach package_key { file-storage, directory, general-comments, forums, notifications, acs-mail-lite } {

    set spec_file "[acs_root_dir]/packages/$package_key/$package_key.info"

    set version_id [apm_version_enable [apm_package_install -load_data_model 
                                            -callback apm_ns_write_callback 
                                            $spec_file
                                       ]]

    set main_site_node_id [site_node::get_node_id -url "/"]
    set main_site_package_id [site_node::get_object_id -node_id $main_site_node_id]

    site_node_apm_integration::new_site_node_and_package -name $package_key 
        -parent_id $main_site_node_id -package_key $package_key 
        -instance_name $package_key -context_id $main_site_package_id

}

apm_ns_write_callback "
Done.

"