Just to end this chain as well.
This is the second thing that has turned into a total NO GO.
Again, just like in relation to Theme adjustments that I also had huge problems with, this only proves to me that without specialised knowledge one cannot get the simplest of things done.
I've tried everything, read tones of documents (most of them totally useless as clearly written from the position of knowledge) and nothing works.
Again, at least I tried and can now move on with clear conscience - without the icons, obviously.
Still, thank you to those who tried helping out. Time is a valuable commodity and I do appreciate your efforts.