I have restored my last theme, as well as some images, courtesy of my backups and a fresh backup that I got from Priorweb, my hosting provider, who have been very helpful and have reacted promptly.
(I pay them good money for this, of course, but it always nice to be helped along quickly and efficiently).
So. The website is back up, Google has done a site review and have deemed me clean of adware and infectious spirits, and I hope to stay that way.
The code is obfuscated ofcourse, but I would like to plough through it and understand it some more, what it does. I’ll let you know if I find the time and motivation (both of which are in short supply for the moment, work taking up quite a bit of my spare time and going to take even more next week.