For “Reset to None” you should be able to disable or delete the FX from the FX chain. Click on the FX box at the right hand end of the clip.
As for the chroma key problem, you might try using the key more than once. In other words, key for the basic green. They key again for the green that remains. You may have to do this a couple of times; if you do it carefully you can probably get rid of all the green halo.
Jack
VideOccasions
