Fix the crash when moving the focus to the Desktop when playing in full-screen
Fix the issue that skill's rank limit gets unlocked when playing MAIN EX mode.
[Other fix]
Now the the game prompts the error when DirectInput initialization fails.
* This game requires DirectInput, but since some Windows doesn't have them as default, please download it from Microsoft page (Steam version will install it automatically)
DirectX End-User Runtimes
https://www.microsoft.com/en-us/download/details.aspx?id=19743
Now the game won't accepts the keyboard input when the game is not focused.
This will prevent the game reacting the input when the user using web browser or anything.