Certain commands for editing in Photoshop not available

[PeterAit]

I am using LR5 and have Photoshop 5 installed. When I select 2 more more images in LR, right-click, and select Edit In, certain commands on the next menu are not available (they are displayed but grayed out): Open as Smart Object in PS, Merge to Pano in PS, Merge to HDR in PS, and Open as Layers in PS. The Edit in Photoshop.exe command is available and works as it should. Any ideas?

[PeterAit]

OK, problem solved. Turns out I was using Photoshop as an "other external editor" and once I restored the registry keys specifying the path to PS all the commands came back.