Menu creation.

Thank you for your response =)
but the question remains.

I don't understand xdb files at all; I don't know what they are, what they do, and what is required.
For example, in the mod by Xazardous, there are the following files:

Arenas -> Interface -> MainMenu
Camera-idle00.xdb
MainMenu.(ArenaDesc).xdb
UI
Background.(BackgroundSimpleTexture).xdb
MainMenu2.(WindowScreenShared).xdb

I have a hard time understanding what they are for.
Only the texture references are clear. Where can I find information about the other abbreviations?