I spent ages solving this problem, so here is a problem and solution in one post…
I was struggling with the first beat of each Main Drum Loop on the way out of the Intro. In the pre-loaded rhythms there is often an accent on the first beat of the Main Drum Loop. Take Rock 1 as an example. The Intro is a one bar tom roll fill. The Main Drum Loop is then a basic rock beat one. When you play the rhythm there is a crash cymbal accent on the first beat of the Main Drum Loop in the first bar only. I wanted to take it out. It does not appear either at the end of the Intro or at the start of the Main Drum Loop.
The other side of this problem is that in beats that I wrote from scratch, the kick drum on beat 1 of the Main Drum Loop would be missing the first time that bar played.
The solution to these problems lies in the intro. To solve the first problem, edit the Intro in Rock 1. Increase the Total Bars Count (left of screen in BB Manager) to 2 bars. You will see that at the start of bar 2 there is a sneaky extra kick drum and crash cymbal. Take them out, then reduce the Total Bar Count back to 1. Problem solved.
To add the missing kick drum at the start of your own created rhythms, do the above in reverse… add an extra bar to the end of your Intro; add the accent that you want at the start of the Main Drum Loop (i.e. first bar only), then reduce the Total Bar Count of the intro back to what it was before you added the accent.
Hope that saves someone some time!