Unfortunately you have discovered the one real serious flaw in an otherwise excellent program. RB does not work with plugins like EZDrummer or my Jamstix or any other plugin that can create their own parts. I don't know the details but it's something to do with VST implementation. As you noted just using your EZD as a sound module for prerecorded drum tracks works fine, it's the creation part using EZD's own grooves that doesn't work. For that to work RB has to tempo lock with the plugin and it can't. For over two years now the guys at PG music have said they're aware of the problem and are working on it but so far nothing. Virtually every other important problem has been fixed fairly quickly except this one.
We can only conclude it must be really difficult if not impossible to fix because at one point Peter himself said they were working on it and every other thing he's said you can take to the bank.
I really want my Jamstix to function properly in RB but I've given up complaining about it and trust me a year ago I was all over this subject along with a few others but it hasn't been fixed and that's it but please feel free to put a new post on the wishlist about this. RB is still my favorite program so whattyagonna do?
Your question also mentions Biab. It only has one midi output port so if you try to use EZD with it every part is going to sound like drums. You have to use one good multitimbral synth that has all the instruments and then move the song to RB to use different synths.

Bob

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