What exactly did you type in? I'll give you an example of my own maps:
I made a weather file and saved it under Novum. When I type in "Novum" It will work. However, if I type in Novum.cycle or Novum.sky it won't work. Another issue might simply be that it didn't save. Check under your Feralheart folder in Media>Sky to assure that both the weather and the sky file are still there.