Hello and sorry for my poor English, I use a translator

.
I'm a beginner in the repack world, but I really want to learn.
This forum is great and this aio tool too.
I would like to know if it was possible to create your own installer design with this aio tool or with another software.
If someone could tell me if this is possible and how to do it because with the install creator or the design creator I don't see how to import template in the compiler provided in this tool.
Thank you in advance for your help !