having this same issue today...no matter is i click participate or not participate...the window closes but all photoshop features appear greyed, and cannot do anything with it...NOTHING...i have a major work to deliever tonight...and this f****problem is going to make me loose this opportunity...I AM DESPERATE!
Sounds like two totally different problems to me.
It may help to reset Photoshop's preferences to defaults... You can do this by pressing and holding Control - Shift - Alt (Command - Shift - Opt on a Mac) immediately upon cold-starting Photoshop. If you get the keys down quickly enough - and you have to be really quick - it will prompt you to confirm deletion of your current preferences, which will lead to the establishment of a fresh default set. If it does not prompt you, you haven't been quick enough to get the keys down.