New mid-2017 MacBook Pro 15" with 1TB SSD and 16GB RAM.
Mac OS 10.12.5
LR CC 2015.10.1
Helicon Focus 6.7.1

Export 4 DNGs from LR to HF.
Render. Save. Quit HF.
Return to LR. Upon return to LR, LR throws an error
Unable to Export. An internal error has occurred. AgImportSession ...