To put the RTB and/or Broadcastable validations, you have 3 ways :
1) When you generate a master, a window with the item data is displayed. The RTB 
and the Broadcastable 
icons are available. Click on them. The icons turn red.
2) In the Browser, in the RTB and/or Broadcastable column, on the sound. Click on it (or double-click, according to the configuration), the icon(s) is/are displayed.
3) In the Browser, select the item to validate and press Ctrl + R to put the RTB validation and/or CTRL + B to put the Broadcastable validation .