I was planning to save this writeup for something outside of Twitter later, but after seeing that trashy article, I now feel compelled to fully debunk the "Nagano created Five Star Stories because he was upset at Tomino for not letting him do what he wanted on L-Gaim" (1/?) 
To start with, when I refer to "L-Gaim" here, it is directly in reference to the 1984 TV series as directed by Yoshiyuki Tomino, not the various supplements made for it that Nagano worked on that will be of much importance to this discussion. (2/?)
First and most importantly, Nagano has no animosity towards L-Gaim or its production. In fact, in the Forbes interview, he remembers that when the rest of the staff was switching gears into production for Zeta Gundam, he felt a bit sad that L-Gaim was concluding. (3/?)
Now I'm going to have to bring up Five Star Stories- and this is very important: FSS did NOT start with the manga in 1986. It was first published in one of the 1985 L-Gaim mooks while the show was airing, LABELLED as "Five Star Stories"- complete with a timeline. (4/?)
I go into more details about this mook on my Tumblr, but essentially, this mook is Five Star Stories in its very first form. It was meant to be an alternate retelling of L-Gaim, as Nagano would have liked it, complete with new designs. (5/?) the-bang-doll.tumblr.com/post/150478701…
This was not unusual at the time in the 80s- for instance, Yutaka Izubuchi's "Aura Phantasm" was to Dunbine what Five Star Stories was to L-Gaim, meant to be a different interpretation of the source material by someone worked on the show. (6/?)
The published of this mook, Kadokawa, noticed Nagano's "Five Star Stories", and were very interested. As a result, they proposed to him to create it as a standalone work, originally as a storybook, as Nagano recalls in the Forbes interview. (7/?)
At the same time, Kadokawa was also preparing to debut its new anime magazine, "Newtype". As a result, the editor-in-chief at the time (and current President of Kadokawa) sought out Nagano's talents to work on the magazine.
The rest as they say, is history. (8/?)
The rest as they say, is history. (8/?)
(of course, before FSS was published in Newtype, Kadokawa encouraged Nagano, who had never serialized a manga on his own before, to practice for a year with a series of his choosing- resulting in Fool for the City, originally based on a short comic he drew in the 70s) (9/?)
tldr; Five Star Stories was the result of a publishing company being interested in Nagano's work and wanting to give him a full platform for it. It has nothing to do with Nagano's feelings working on L-Gaim, which remain positive to this day.
One final thing of note- as Nagano himself said in the Forbes interview, what was in the mook that became the foundation of FSS were Nagano's original ideas for L-Gaim that existed before the show started. They were not made in response to or because of Tomino's input.
