Everything the VST plugin does or does not do is listed in one of two places.

The new User Video https://www.youtube.com/watch?v=9rJuNoo7rqk

Or

The 41 of Your Problems Solved! List of the 41 Requests Fulfilled in Band-in-a-Box® 2020 DAW Plugin Version 2.0. https://www.pgmusic.com/bbwin.plugin.problemssolved_2020.htm

According to the second option, the bar settings are supposed to be honored. Did you use Bar Settings to make you changes?

#3 The new Band-in-a-Box® styles are great but I'd like to be able to customize them and replace some tracks. Can I do that in the Plugin? The Plugin now supports replacing style tracks just like Band-in-a-Box®. You can customize your style or open a saved song with a customized style in it. For example, if you load a SGU/MGU song saved in Band-in-a-Box®, you'll now see the customized settings that you used in the song, such as custom track settings.

#9 How about bar settings? The Plugin now launches the Band-in-a-Box® Bar Settings dialog and allows you to set bar specific settings. These include things like changes of time signature, tempo, volume changes (mute, un-mute), etc. for instruments.

Of course you could do this old-school like Noel has instructed, but then why would we need the VST? crazy

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