@Francesco,

I'm also trying to figure this out for Aeroo for Odoo 8.0. Did you ever find a solution?

@Francesco,

You can use the following OCA module to dynamically create the filename for the report:

https://github.com/OCA/reporting-engine/tree/8.0/report_custom_filename

I haven't figured out how to add the invoice number as the filename yet, however it is on my TODO list. I'll write back here once i've figured it out.

If you are familiar with python and Odoo models and fields I believe you may be able to figure it out though, as it uses python logic to create the filename.

If you figure it out please write back here so others can benefit also.