Can someone teach me how to change the source codes for mod folder in 'Mod selector'?
Is that the xml file for mod zip files need to be rewrote?
Don't quote me on this one because I'm far from being a hacker, but I believe it depends on the specific hack. Sometimes both, sometimes the .xml. For example, to disable debuffs you'd only need to change the .xml to tell it where to add what's in the .txt (which needs no modification), in other cases like no allied particles you'd need to edit both.
Again, this is from personal experience and by no means facts. It'd be great if one of the pros could correct me.