CS6 no longer available as editor from Lightroom

[Peter S]

I have Lightroom 5, CS6 and the Photographers CC Programme as well as Photshot Elements installed on my iMac.
Up until recently I could choose to edit in either CS6 or Photoshop CC although Elements was listed in my Preferences as the Alternative Editor.  The choice of CS6 now seems to have vanished.
Is there a reason for this?
Is there any way I can get it back as an option in the Lightroom dialogue without deleting the Elements option?

Many thanks
Peter

[Denis de Gannes]

Lightroom will choose the latest version of Photoshop as your primary editor. In your case this will be Photoshop CC, you cannot change this. However you can add PS CS6 as a secondary editor. You can only have one primary editor but you can have multiple secondary editors.