I used to question this a lot when I first started downloading mods try downloading a anti virus app to protect your device so you can download safe mods
Sorry for late response I used to have this problem before I figured out how to download the mod I tried figuring out how to do it and Its been so long since I played this game so I think when you go in zarchiver you have to look for the one that says fmod and if it's your mod name and it doesn't show fmod then i think you have to open up the file and it will say fmod inside the file
Do it on the editor then go to the file without the zip and tap one the mod u were Dowland of the name then it would say successfully distilled mod only in editor I tryed and got my plane pack ngl