[Oddsodz]

As silly as it may sound, "Refresh/Re-scrape" the TV show information, Then run "Artwork Downloader". If you don't have some season posters by then, That means that "TVDB" website does not have a season poster for that TV show. So you will have to make your own and add them manually to the TV show. The last thing you can try is to "Export/backup" the video library and make sure you say yes to the options for separate files. This will put the season posters in the right places for the skin to see them and use them. The Skin will always pull from the TV show folder if the files are there and "Artwork Downloaded" has been run once.

Yes I know it seems wrong/weird, But trust me on this. It works.