Bryan,
I’ve been experiencing something the same or similar.
I upgraded to PL 6.10 when alerted to a new update on 27th Sep, and have been away from 3rd-10th October. I’ve just started processing the images from my holiday and run into the same issue of the CPU maxing out at 100% for around 10s each time I select a different image from the filmstrip in Customise mode. I then tried an export of one image which took 79s (DeepPrime noise reduction) compared to the ususal circa 30s. I could see the graphics card wasn’t being used during the export and the CPU was maxing out at 100%.
Although my graphics card is old and slow, and only marked as “partially supported” (NVIDIA GeForce 750 Ti) I wasn’t having this problem with PL 6.9 or any earlier versions of PL. I’ve also been using the EA versions of PL7 without any problem.
I’ve now just uninstalled PL 6.10 and reinstalled PL6.9. The same image now exports in circa 30s as before, and I’m not getting the CPU maxing out as I move between images. So it looks like the issue was introduced in the upgrade from 6.9 to 6.10.
I’ll raise a support ticket, and mention yours, and provde any response / update here.