For those who don't know, this is how Winx Club came to Nick and stuff.
Winx Club was originally made in Italy. It was being produced by Rai Fiction and Rainbow S.p.A, and directed by Iginio Straffi. (Layla was actually Aisha here, Rai EN changed it to Layla.)
Winx club was already airing in English in England or around that area. (I know it was in Europe for sure.) In Europe, they aired it all the way to the end of season 4.
For whatever reason, the creators of Winx Club wanted to expand Winx Club to America. That's where 4kids comes in.
Winx Club was aired on 4kids only until the end of season 3. This was because:
(1. 4kids license for Winx Club expired.
(2. The creators of Winx Club did not like the way 4kids dubbed.
(3. All of the above.
Done with 4kids, the creators sought out a new partner in America. This is where Nickelodeon comes in.
During this time, the Winx Club fans all around the world eagerly awaited season 5.
Since the creators of Winx Club wanted to hurry up and dub season 5, they teamed up with Nick to make 4 specials to make things go faster. This is also probably why they cut out a lot of parts so each would be 45 minutes long.
Nick then dubbed seasons 3 and 4 and also Secret of the Lost Kingdom, and later while season 5 was airing, they dubbed Magical Adventure. (Which Nick did horrible with because they made this just like the 4 specials, only with Believix. Just my opinion here.)
Nick now is airing season 5, and some say they will be airing episode 24, Saving Paradise Bay, August 25th.
They have also started dubbing for season 6, as Matt Shively (Sky) tweeted a picture of himself dubbing season 6 episode 1: Inspiration of Sirenix. (Season 6 will air Spring 2014 and the trailer will be sometime in October.)
There you have it, folks.