I suppose you could call this a little ocd, but just out of curiosity, is there a file or something where things like plasmoid positions, sizes, settings, etc. are stored? I had a nice set up for my desktop, but then for some reason or another I turn on my computer and it has reset to the default desktop...
I would love to be able to back up everything so that should something like that happen I can quickly recover it, or perhaps if I wanted to play around and try and find something new, I could always just have a 'reset' button to undo whatever I messed up.

Thanks in advance!

There have been several occasions that I wanted to know something about the KDE configuration files. On those occasions I open a GUI file manager like Dolphin, enable 'View Hidden Files', and walked through the .kde tree opening text files with something like hexedit to see the contents. I didn't always find what I wanted to know but I learned other things about the KDE configuration files along the way.

Give it a try.