Yes, Maeve broke free of her narrative.
(Warning: Answer is a spoiler for most of Westworld Season 1)
The terms being thrown around by the show haven't been clearly defined so we don't know if she has "free will". You could argue that she's programmed to want to see her child again and is locked to a script no matter what. Do humans even have free will? This is beside the point.
That she escaped the "Escape Narrative" is a given, considering the fact that she got off the train at the last second. You suggested that leaving the train could have been part of the narrative too. Beyond the fact that the theme of this episode was about the hosts gaining self-awareness and breaking from their narratives, the writers told us she was meant to escape the park in her earlier dialogue with Bernard.
Bernard: You can even see the steps you're supposed to follow. You're to recruit other hosts to help you. Then you're to make your way to the train.
Bernard: Then when you reach the mainland--
Maeve: Bullshit! No one's controlling me.
Then she breaks the tablet. It's quick and easy to miss. Right before that he shows her the tablet with part of the programming visible. It says "DECEIVE", "COERCE", "RECRUIT", "ESCAPE", and "MAINLAND INFILTRATION".
It's possible the writers will overturn all this in Season 2, but until then the fairly explicit intent was that Maeve, like Dolores, has broken from her loop. There is no evidence that getting off the train was part of the narrative.
As for "solving the maze"? Assuming you mean "gained self-awareness", that is a different answer which we don't know yet.