I'm using MZ. I have all of my tracks preloaded and they are all the same length so I can use "continue" to fade between them seamlessly. I want the overworld theme to fade into the battle track without missing a beat. I don't need to use random encounters, so it's fine if this only works with event encounters.

How do I make this work with battle BGM? I tried playing the battle track before a battle starts using the plugin command, and setting "Database: System 1: Music: Battle: None" but this doesn't work. It just starts playing my battle track when I call the plugin command, then mutes it when the battle starts. I guess the BGM "None" overrides the plugin command. 

Also, I get this error when the battle ends (before leaving the battle):

btw, this plugin works great in general. Even if it only works for events, I still love it.

Update: if I have a battle BGM set under "Database: System 1: Music: Battle" the same error occurs at the start of battle.

If I have no BGMs set under System 1, the error still occurs at the end of battle

Update: I fixed it! Jay_SoundtrackManagerMZ.js has a naming error.

Find "playLoadedBgm" and replace with "playLoadedBGM" and everything will run fine.  This takes care of the "not a function" error.

Meanwhile, the overworld theme can easily "continue" into the battle theme. When you run the plugin command Load BGM, leave Alias blank so the alias will be the same as the track title.  Set "starting point=continue." Now you can choose your tracks with "System 1: Music" or "Map Properties: Autoplay BGM." As long as the track has the same name as the alias chosen in "plugin: Load BGM" that track will always use the settings you chose under Load BGM, including "continue."

...Okay.

I didn't even get a notification about this topic until you posted your solution, but you do appear to have figured it out, so... I'll just put out that bug fix, I guess. And yes, this plugin is meant to override the regular music commands when you've got a preloaded track, specifically so that you can override things like battle music. I use MV more, so I guess an MZ bug would have flown under my own radar, so sorry about that.

I wonder why I even capitalized it in the first place. My MV plugin has it as playLoadedBgm in all cases. *shrug*

EDIT: Though, looking at it, I found another bug in MZ. Might be a similar bug in MV? I'll look into it.