make sure both the base object and cutter objects have adequate mesh density to bend.

1. choose a category. 

2. make a mesh of your liking and rename it something unique. 

3. take a screenshot or render of the object, name it same as object name in jpg format.

4. save the blend file same name as the object name.

5. put the blender file and picture into the relevant folder and press refresh preview in addon preference.

you can now use it every time blender is open.

The scifi category is a bit different from others. it utilizes patch mode on a single quad face. Therefore, during face selection, make sure it is generally a square shaped, so that the script can reduce it to a single quad face. if all things failed, you can always select a single quad face to start and scale it up.