Is it possible to map filefield somehow? I tried mapping fid, filename, uri, full URI created with hook_services_client_data_alter hook, but still it doesn't work.

I found that service_raw module has attach_file action, but after I looked through the code, it only appears on webform_submmision_save form, so this function is not available for regular nodes.

If it is not yet possible to map filefields, then this is a feature request. Also a request for some documentation about mappings, available features etc., because I believe it is hard to configure this module for new users.

In a meantime, I am probably left with writing some code (hook) on my own module. The idea is to get external file URL with services client, and then use regular drupal functions to save that file and attach it to the node on node_save event.