There are no complicated rules for writing general fan-fic here - just be true to the characters, and keep it suitable for all readers as we have some young members.
As a fan-fic writer myself, I would recommend getting yourself a beta reader to check your work. It is impossible to proof read your own writing as you read what you expect to see, and it is easy for typos to slip through.
As for the 'Virtual Seasons' - if you want to write for that you need to submit your story to MJ Cogburn who is the editor. She will check that it fits in with the series as it stands, and advise you if you need to make any changes, then she has the ultimate decision as to whether or not it 'airs'.
Good luck with your writing!
As a fan-fic writer myself, I would recommend getting yourself a beta reader to check your work. It is impossible to proof read your own writing as you read what you expect to see, and it is easy for typos to slip through.
As for the 'Virtual Seasons' - if you want to write for that you need to submit your story to MJ Cogburn who is the editor. She will check that it fits in with the series as it stands, and advise you if you need to make any changes, then she has the ultimate decision as to whether or not it 'airs'.
Good luck with your writing!