While Sider (a more advanced server) eventually replaced Kitserver for later PES titles, Kitserver 13 v1.04 was the last stable iteration for PES 2013 that supported "Memory Wall" breaking, allowing scripts to access memory addresses beyond the standard 2GB limit (relevant for the 4GB patch often used alongside Kitserver).
Instead of manually importing textures into the game’s proprietary .img files (a process that often corrupted the game), Kitserver allows you to simply drop folders of images (kits, faces, boots, balls) into a "GDB" (Global Database) folder. The server hooks into the game’s memory at runtime and swaps the default assets for your custom ones. Kitserver 13 1.04
), intercepting data calls to load custom assets from an external directory called the GDB (Game Data Base) While Sider (a more advanced server) eventually replaced