A) Double Click on the Inner Tube Game Window that is on the Primary Monitor and Inner Tube will return to the secondary monitor.
Maximize the game window by using the Maximize icon in the upper right hand corner of the game Window.
Avoid Double Clicking on the game window underneath the Title bar and it should be remain on the secondary monitor.
You can also double click on the Title bar of the Game window and the game window will Maximize / Restore Down.
* The Title bar is situated at the top of a window
