Bump, still not resolved. Any ideas are welcome, thanks!
I've not experienced the symptoms you describe. However the Blur Gallery does use the Graphics Processor, so I would try:
1. Alternative drawing modes in Preferences - Performance - Graphics Processor settings - Advanced.
Try the Advanced , Normal and Basic settings and see if any make a difference.
You will need to restart after clicking OK to see the difference
2. Check your video driver is up to date (don't rely on Windows updates for this - go to the manufacturer site)
Thanks a ton Dave, that did the trick! I had to switch to basic mode to bring up the preview, which doesn't make a lot of sense to be only because I have a brand new mac with an i7 processor and Intel Iris Pro Graphics 6200 1536 MB, plus 16 GB of memory. Maybe there's some kind of allocation limit/setting on my graphics processor, but at least now I know where to look.
Thanks again for the help, you're great and the issue is resolved!