Missing something

While trying to create a new controller for the admin control panel (I've developed a custom ups shipping integration that provides me the required labels for printing and so places the picking up/return order) I encountered I wasn't able to this.

Let me explain myself.
I was able to extend the functionality of the sale's controller to achieve my purpouse (displaying the custom buttons and tracking information) but I wasn't able to create a new controller that I could access by itself. Meaning "admin/index.php?route=custom/controller" always returned on a "You don't have permission to view this page" or something like that error.

I'm able to create controllers on the catalog folders but not on the admin folders which leads me to believe there is either a list of admin controllers somewhere that I've missed. Or that I need to include some code in my controller so that OC knows it exists. Like maybe include it somewhere in the system folder?

I'm at a loss at the moment and while it's really urgent since I've solved it by just extending the sale/order controller I'd rather have it on a separate controller instead of modifying one.

Thanks in advance.

did you go to the admin user group of your choice and give it permission to custom/controller?

That's exactly what I was missing Xsecrects. Opencart should have a stackoverflow'ish site to reward knowledge.
Thanks again!