Posts: 11,250
Threads: 195
Joined: Feb 2011
Try to do the first step with the holy grail wizard only - skip the color corrections for now. Just Save Metadata, transfer it to Lightroom (all) and render after having done the Holy Grail Wizard. This should normally give you a mostly perfect transition without the pumping.
Posting a screenshot of your preview panel in LRT after the HG-Wizard might help us as well to understand what's going on there.