Hi,
You can disable screen scaling in the properties dialog of the app(Flash.exe).
Go to the installed folder of Flash (C:/ProgramFiles/Adobe/Adobe Flash CC 2014) and locate Flash.exe.
Right click on the exe and invoke properties dialog
In the properties dialog go to compatibilty tab>Settings and check the option "disable scaling on HidDPi setting" and try.
Hope this helps.
Thanks,
Sangeeta