I haven't bought De:Flicker yet. Im just trying to see if it will work for me first. It seems that there is little to no tutorials on how to use it in FCPX. The application i use it for is mostly flickering lights at wedding receptions. If i understood it a little better in FCPX and could see that it would work for me i wouldn't mind shelling out the money.
So far i have figured out how to eliminate most of the flicker but it leaves crazy artifacts on any moving subjects.
The last 4 are same for all apps as it's the same thing
Note it's hard to visualize with text
If you hit the support tab on our site, and use the Xontact Support form it will send you info about uploading a sample movie for us to look at
From your description you are using a shutter speed that does not match 60 Hz, if the issue is rolling shutter bands (a stripe of a different color level moving slowly across screen) this is harder to fix...