It looks terrifying to begin with when you look at advanced materials like that, but once you break them down into sections and recognise what each node is doing you’ll be fine.
I was the same with UDK, but once I went through them to see what was happening it all became easier. My dissertation was working with blended normal maps and SSS, I hadn’t done anything as complex as that previously but once I understood what was happening it was all fairly simple!