It's up to you to create your categories, create your methods from the File Manager, and then move your methods into the categories of your choice by right-clicking (context menu) on the method(s) of your choice and then "change the categories", all methods and compressors are in a default category called "Not defined".
I allow myself to quote the work of
Panker 1992, you can download the compressors that it has assembled in a folder "
masked Data Compressor 2.5" In this folder this finds "arc .exe", "arc.ini", "arc.groups", as well as external compressors, this type of folder, Bringing these files together, I call this folder the workspace, to define this working folder, you must populate the path of the file "arc .exe" which is located in the folder "masked Data Compressor 2.5", you must open "Tools > Settings > Arc file", use the browse button and select "arc .exe", by default a folder named" include "in the application directory will synchronize if no workspace has yet been populated.
ps: I wanted to create an application that allows the user to create his own methods and categories as he wants, this brings a certain touch of dynamism unlike the application that imposes a defined number of external compressors.