OMG you are a genius! That does indeed work 
TBH I’d just shelved messing around with Groove Agent recently as the issue was aggravating me to enough to the point where I wasn’t getting work done because I was fiddling around trying to fix things. Although I was still able to drag in and layer my own samples from the browser tab, I really prefer to layer samples from the Steinberg collection that I have spent a lot of money on.
It will be interesting to see if support ever get back to you 