Hello,
I had to do this implementation as well.
To change the filename and also force the file download I copied the FM ALEWEB_DOWNLOAD and change to always use the subroutine aleweb_download_old. And I changed this subroutine at line 42:
content_type = 'Content-Disposition: attachment; filename=[filename_you_want].[ext]; Content-Type:'.
The content-type must be right according the file (eg. application/xml)
Setting this header you are able to change the filename.
Hope it's still useful!
Regards,
Filipe