In the texture type selection, you can choose what kind of texture you want to load. It should look like this:

Currently, there are 4 types of textures: normal textures, bow textures, crossbow textures, and animated textures. As the names suggests, bow textures are for bows and crossbow textures are for crossbows. Normal textures are for all other items. Animated textures are for non-bow items that need an animation. As you can see, each type has its own button:

• The 'Load simple texture' button will take you to the texture edit menu where you can choose a name and select an image.
• The 'Load bow texture' button will take you to the bow texture edit menu where you can choose a name and image, but also select images for the pulling textures.
• The 'Load crossbow texture' button will take you to the crossbow texture edit menu where you can choose a name and image, but also select images for the pulling textures and the images for when an arrow or firework rocket is loaded onto the crossbow.
• The 'Load animated texture' button will take you to the animated texture edit menu where you can configure an animated texture. Animated textures are texture like fire that can change every frame.