Okay, beta 3.0, release 2 is now available.
You can sort interface contents alphabetically, manage multiple controls/elements (no editing yet, but it's coming), and a few other additions such as the status bar (which will be replacing the annoying information alerts by displaying messages quietly).
The backup system has been improved by saving on each action (keeping it up to date instantly). There's quite a few bug fixes in there too, and I've also added comments throughout the script if you're interested.
Note that this will probably be the last beta release, since by the next one, I'll probably have it finished, so it won't be a beta any more.
Just need to sort out presets and editing multiple controls/elements (might have to scrap the builder idea, unless anyone has some example code I can try out for drawing on windows and stuff).