important note in win 10. Flash player in that browser is managed by windows updates.
Although I am not on my work machine which is windows 10 atm. I have not run into any issues out of the box when I upgraded to windows 10 pro at my organization. Flash worked fine, so I am a bit puzzled how yours is messed up already as I did not have to make any settings changes to get it to work on the test flash page.
Did you mess with the ActiveX filtering?
Why don't you go here, and see if it works: http://www.adobe.com/software/flash/about/