Before you enter the preset maker, have your username in the box exactly how it appears in game. Make sure that there are no (1) or (2)'s of the preset parts, it can't be a copy. Also make sure you are giving your only the preset parts and having them put it in the FeralHeart>>Presets folder. You must also restart their game to see it.
I found this on another topic written by moderator Kynvuu but edited it so hope it can help! Credits go to kynvuu for writing the post in the other topic I found.