Sims feet disappearing when attempting clear part of shoe

The boots you started a package from were split in three to hide or be hidden by bottoms to not conflict with them . Try your shoes with a few maxis skirts and you will see a portions of legs disappear.
- open your blend, in uv editor enable sync and select these uvs, in 3d view press P - Selection to separate;

- select feet, toenails and those separated soles, in 3d view join with Ctrl J;
- give the joined meshgroup cut 1;
- select the heels and give them cut 0, save;
- in s4s main menu click on CAS and paste yfShoes_CalfShearling in the search bar, start the package from it, making sure to overwrite the original;
- import your blend files and textures;
- in the warehouse select all geometry resources of heels and change the shader to Simglass;