I no longer own a LeBass preamp but I believe if you put the Cab M in effects loop it will be in the LeBass DI output. I would put the Cab M last in ths chain. That is how I currently use it on my board.
Tuner>Whammy> DG Compressor>Aguilar Fuzz>DG VMT OD>DG B7KU>MXR Envelope Filter>Source Audio C4>Mesa Subway DI+>Cab M+
I'm still a noob with the Cab M+ but this Friday Im playing my first Cab M ampless gig with a FOH engineer and I have a bunch of PreSets I made to try out and see if 1 works well for the room.
Thanks for the response. You are right. Putting it in the effects loop is the same as running it last.
Please update us on how your gig goes!