When you Edit in Photoshop in Adobe Photoshop Lightroom running in 64-bit, using the Merge to HDR, Photomerge, or Open as Layers options, and you have more than three files selected, Edit in Photoshop fails.
When you Edit in Photoshop in Adobe Photoshop Lightroom running in 64-bit, using the Merge to HDR, Photomerge, or Open as Layers options, and you have more than three files selected, Edit in Photoshop fails.
This issue was solved in Mac OS X 10.6.2. You can update Mac OS X 10.6.2 by going to this location:
http://www.apple.com/support/snowleopard/