It worked like a charm, thanks you all guys!
I just describe briefly what I did if there's someone newbber than me at quakec (difficult but possible 

 )who's trying to do something similar
First of all I created a func_button with key 
target and value act1 then I created an entity (I used a player start and changed after the classname)with classname play_doghost and 
targetname act1
I make 
target and 
targetname bold just because they at first seemed to me difficult to understand!
a line will appear to emphasize the connection between the func_button and the entity
the code Nahuel kindly posted is autoexplanatory: the  play_doghost function is called inside the editor and executed
Thanks again folks!!