yes I have the same problem, concierge not much of a help either. asked to download software again.
It appears that the OS updater is corrupting PS CS5 if it was installed prior to updating to Yosemite. Looks like reinstalling fixes the issue
If you want to try and reinstall, you can grab a CS5 installer here: http://helpx.adobe.com/creative-suite...
Or any older versions here: http://www.adobe.com/downloads/other-...
It's probably a good idea to restore your prefs, too: http://blogs.adobe.com/crawlspace/201...
This did not work for me. I have CS5 Creative Suite standard I downloaded from the link you gave. I get the same message.