Hey Ronin, in the model path you simply point to the base model and in your textures is where you define the next states.
For example, your textures would be named as following
mybow.png
mybow_0.png
mybow_1.png
mybow_2.png
With your model path directing to the base mybow.png and IA will handle the others.
For more information and the other valid states for crossbows etc… see this wiki page: https://itemsadder.devs.beer/plugin-usage/adding-content/item-states/using-filenames*