1.Download your filter.
2.Drag it into the filter folder in your mcedit folder under the one heading:MCEdit-0.1.1.win32 or something like that (it should be the top one, avoid schematics and serverjarstorage).
3.Go onto MCEdit.
4.Mark a space and use the Filter option.
5.Click on the big yellow writing and choose your filter that you just downloaded.