Does anyone knows how to use this OOTB functionality :
I want to use the native operation which allows to hash and replace the names of the images in the emails before uploading them to the front servers, except that I want to upload them to a different image server (inhouse image server)
I've never used this, so I don't have a working example. But basically the "Manual publication mode" allows you to use a script to upload files from the Campaign server to any other image hosting server. In your case the script needs to perform the needed modifications to the filename using the methods and functions available in the script language; then upload the files to the desired servers.
I've never used this, so I don't have a working example. But basically the "Manual publication mode" allows you to use a script to upload files from the Campaign server to any other image hosting server. In your case the script needs to perform the needed modifications to the filename using the methods and functions available in the script language; then upload the files to the desired servers.