Ok here's what you need, full overview lol.
Step #1
Read ALL this again, especially this 3rd post about naming and saving.
If you just not sure how to quickly make a new file, right-click anywhere in empty space (desktop or when viewing contents of a folder), highlight
New ►, then left-click "Text Document". Rename it proper, open it with notepad and insert the proper text from the link above.
Step #2
Copy/Install/Move all interface .xml or other files to your
folder within this directory: C:\Program Files\Sony\EverQuest II\UI
So if you name your UI folder Iroxxorz, all interface files must be in C:\Program Files\Sony\EverQuest II\U\Iroxxorz
Step #3
C:\Program Files\Sony\EverQuest II
This is where your file named "eq2.ini" should be and is the file that loads the UI for you.
If your file is showing up as eq2.ini.txt rever to step 1