Riffer Start Playback with DAW

[ral8667]

I'm using Reaper with a looped measure of drums.

I have Ample Bass P 3.6.0 in another track and am using the Riffer feature. I'd like to sync Riffer with beat 1 of my looped section so that when I start playback in my DAW, the current riff will start playing. I assumed the "Riff Sync Toggle" option would do this, but it does not.

I also use Ujam Royal Bass 2 which has this feature. It's super handy to quickly find a suitable bass pattern.

Am I missing this feature, or does it not exist?