Maat I was thinking you could implement a system where instead of editing the mod directly for strings or ints floats whatever, you could, for example, replace the .30 in the autonexus with %f="nexus percentage"%d=".30". %f would tell your program that the type is float and in quotes is the name that the GUI will display and the optional %d= would contain the default value. In your GUI, as you click a hack in the list on the right would be a textbox containing the default value for each customizable variable, with a label next to it containing the name and type.
What do you think?