I wonder if this is a question that is being obscured by translation.

When Papity changes a style later in the song using F5, he/she writes: "Band in a Box only reminds the first bar style and play it along the whole song" (my emphasis added)

Dan (username MusicStudent) said, and I can verify, that the track names in the Mixer do not change when the style changes. I hear the style change but I don't see anything change in the mixer. Whole new instruments might be playing.

Is that the question here? That the style change works but you don't see visual evidence of that?

And is this really Multisyles, or choosing another style? Papity, you can upload your song (MGU or SGU file) to a free place like Dropbox, put it in a Public area, and post a link to the song here. Then as Dan suggested, we will know for certain.

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