Cameras Roll Rob Kardashian & Blac Chyna's Baby Shower

Rob Kardashian and Blac Chyna's joint baby shower went off without a hitch this weekend ... and a lot's changed for the couple.

Rob showing up at all was a big deal because it was shot for their reality show, and as we reported ... he'd gone back into recluse mode lately, and put back on much of the weight he lost.