I know corners might behave different according to what formation you are using, so I will post screenshots instead of a download, this way you can see too it that you get it as close to my setup as possible regardless of formation.(This was set-up with a 442 formation)
This is nothing new when it comes to the setup itself, I got it from someone on this site but can't remember from who it came originally.
The trick for this to work:
1: Assign your RB to take corners from the right / LB to take corners from the left (this is important as the DR that "stays back" on corners from the right should have the little "TK" mark and vice versa after completing step 3)
2: Set up the corners according to the screenshots
3: When you've set it all up, go back to "set piece takers" and remove all corner takers, there should be no corner takers assigned. (the screenshot is taken after I've removed the corner takers, thats why in the picture both fullbacks are on stay back duty, with one of them having the "TK" mark)
For me this plays out with the short option player getting the short corner, and then playing it short to the "TK" player who is making a run in to the box, either finishing or playing to teammate.
Let me know if this works for you guys, as it is the best corner set-up for me.
This is how it looks BEFORE the corner takers are removed:
Please remember to remove corner takers after setting it up, so your setup is identical to the two first screenshots in this post!