So balancing out the "kind of good" with "really bad" i'd give it a 2/5.
The film's pacing was a little awkward, the opening scene was awkward, but I guess that's what they did back in the day when these kind of things happened. The choice of it to be a musical was also probably super awkward, and I doubt was the original intention. The pacing at the end does seem to drag on a bit, around the last half hour, I was like they could have probably cut out about ten minutes of content. Now, that's enough about the plot, let's talk about it as a musical.
Well, what do you want me to say? It's a musical in its earnest fashion. There will be no more than 60 seconds without music playing in the background or singing, even if the song is only nine words. This was a hardcore musical and being that it isn't a typical musical because it's a biopic, they pulled it off pretty well. The ending was superb and perfect, it doesn't end like a typical. Again, this isn't a typical musical. Also, as a musical, this seems to have more tracks than a regular musical.
I swear there had to be no more than 20 spoken words in the whole film by the main characters. Antonio Banderas' character is just confusing, he's sort of a narrator. Yes, a narrator in a musical. I don't know if he ever actually existed in the film's plot or not, I'd have to research that. His role was hilarious, and he seemed a bit like a troll. He had a hilarious habit of constantly breaking the fourth wall which along with his general character helped break monotony.