Sometimes your OSX blocks Imagink telling you this software comes from an unindentified developer.
To authorize it :
- open "system preferencies"
- go into "security and privacy"
- unblock the modifications by clicking on the padlock at the bottom left of the window and enter your admin password
- then modify the parameter "allow apps downloaded from" by choosing "anywhere"
Now your Imagink app can be launched. Once Imagink has launched one time you can reset the security parameter as it was : the app will always open.