Help in implementing animations for custom items.

[Raggedy]

Hello everybody. I am developing a mod for my studies, and I am trying to implement a new jacket and a backpack. As far as the code is concerned, the items are already implemented in the game and work as intended. But I can't make the animations work, my character keeps wearing an invisible jacket, and when I drop it on the floor, the jacket disappears. I've been trying to use Custom Hat, Armor & Handslot Item Templates by PanAzej to try and implement the jacket. I have replaced the pngs of the tutorial with my own in the folder (you can find the images I'm using attached to the post). 

I know that the code is correct because when I try to use the original animations everything works fine. 

At this point I think that I haven't understood how the Spriter works exactly, and I can't find a proper tutorial for it. Can anybody link me to a step-by-step tutorial, or how to correctly use the custom item templates made by PanAzej?

Thank you in advance! (P.S. The mod is for personal/academic use only, so it is not going to be released to the public) (also it is my first time posting, let me know if I made some mistakes in quoting people) 

Edited April 30, 2022 by Raggedy