This thread is going to be a guide and/or a library for those interested in editing their Fiesta Online UI.
Here you will find several steps that will allow you to find the files necessary to do so, the programs used while editing your UI, and tips/tricks that you can utilize when doing so. If you have any questions or concerns, post below or send me a PM and I will respond to them as quickly as I can.
Disclaimer: This is only going to edit the appearance of your hotbars, inventory spaces, gear spaces and possibly the colors. As well as your icons. This is in no way, shape, or form exploiting nor will I assist in anything such as that. Look elsewhere.
Tip: When performing any of the steps below, ensure you have a copy of the files you are editing. Never work on the source file itself. I recommend keeping your file copies in a separate folder on your desktop to prevent from getting them confused with the others.