This blog will show you how to properly setup GUI buttons and popups. The most common (and easiest) way that people are setting up GUI elements, is to edit existing files such as InGame.xml and other GUI element files (such as TopPanel.lua). This is the bad way to do it, because it will create Mod incompatibility with the next modder who comes along and edits InGame.xml or the same file you're using.
The proper way separates your GUI elements from the existing core GUI stuff, so
Welcome to the second of my Civ 5 mod tutorial series.
To quickly recap on tutorial 1, we covered the basic fundamentals of modding Civ 5. We look at how the backend data store operates, the in-game XML->SQL converter as well as an example of how everything can be tied in. The biggest thing people should've taken from tutorial 1 is that the data store for Civ 5 operates like a big database, with tables rows and columns. A bit like a giant spreadsheet.
This blog marks the first of my long-ago promised Civ 5 tutorials.
Before I go into too much detail of how to mod certain things within Civ 5, I want to cover a basic lesson in the foundations of Civ 5 modding, and how it actually works. If you've read Kael's Modding Guide off the Civ 5 wiki, I can understand your continued confusion as to how to mod Civ 5. Kudos to Kael, but the guide really only covers how to use the tools. I am going to assume you haven't read the guide,