Hello, I have a bug when trying to use the plugin (pro version). As you can see on the image, the text is all messed up. It is strange because your plugin used to work on a previous project. I'm on the 5.4.16 version of EliMZ_Book and 3.2.3 for the BitmapFontPro plug in. Thanks for your help!! 
Viewing post in Hakuen Studio Bitmap Font for RPG Maker MV MZ comments
Hi there!
This is a plugin parameter configuration problem. Probably the amount of characters you put on your bitmap file does not match the amount set on the plugin parameters.
Take a look at this post, it had the same problem https://itch.io/post/5465325
If you are using Visustella, make sure to take a look at the compatibility section on the help file.