Problems with shortcuts

Hi

I´m using GM since 5 days and everything fine, but today I have a mistake

When I´m in safari, and press CMD+H to hide the browser, doesn´t work, with others apps, like itunes works ok, but with calendar, not work again, I don´t know why. Now the shortcut is CMD M, how can I change this??

and other question: if I,m in an app, safari for example, and open calendar, safari dissapears to dock, I only can use 1 app in the screen
If I try open expose, only shows one, and before this mistake, I can see 5 or 6 apps open in the expose

What can I do??

I try create a new user and everything works ok, so is something in my user

Sorry if my english is bad

 

I´m user Admin

If I reinstall Capitan GM and use timemachine backup, the settings I think backup and same problem appears?