[Milhouse]

1 - Successfully automate a process so that all my current movies (well, those for which a CD or Disc art is provided) display that CD or Disc art in my library. Is that possible using my folder structure? ( I know I 'm not in an ideal situation and the requested structure asked by Artwork Downloader, with all my movies in the same directory). I'm just trying to understand how eveything works. If this cannot be achieved automatically, I resign myself to do it manually, at least to update my actual library for all my movies. Then, when I would add more movies, I would do them one by one.

You can do it semi-automatically, using the script in my sig in combination with mklocal.py (on the same github). Search the link in my sig for mklocal.py details (or start reading from here). If you're not comfortable working at a command line, then it's most likely not for you.

This is what I 'm confused with: The "disc.png" and movie_name-discart.png files. What is the difference between the two? Which one is used? Both? Which one is written in a database and what is written exactly?

disc.png is used when you have one movie per folder. However the "movie_name" prefix is required when you have multiple movies in the same folder, as you have. AD only creates (and reads) local artwork using the former naming convention, so any artwork AD downloads will use the same "discart.png" artwork file, which isn't likely to be very useful when you have more than one movie in the same folder. As things stand you are unable to use the "Use local files" option in AD, so leave that disabled, which means AD will only associate your movies with remote (http://) artwork - it won't actually download anything.

And since it's not actually downloading anything, this is where mklocal.py comes in, as it will download that remote artwork (in its original quality, not the crud you will be exporting from your library), and will create correctly named movie-name-prefix filenames, which you can then set on your movies using texturecache.py.

Knock up a simple little two or three line script for yourself that runs mklocal.py/texturecache.py and you can run this script each time you run AD (heck you can even have texturecache.py run AD for you, in silent mode), and then you'll have discart, clearart, whatever-art stored in your local directories, correctly named with the movie prefix, and associated with your movies (replacing any remote urls).

2 - Once my movies will be well tagged with CD or Disc art, if I export my library using separate files, etc. (as mentionned above), will the other networked stations also import correctly my CD or Disc art so that can reflect what I have on my own master station?

This is what I'd like to get but the way to get there is difficult because I don't understand much of the process yet. I read the wiki but I still don't get it. I hope that I have explained my situation well enough.

Sure, use mklocal.py in readonly mode on each client to find the non-standard artwork that isn't already in the library and it will set it for you. You can then pre-load the cache on that client too, if you want.