Chili:
Unless we're at cross-purposes, the R44 - last time I looked, yesterday - has only one engine. Double the number of seats of an R22, but still s/e.
I forgot instruction, long time since I was s/e IFR. "Flying commercially" - meant in the sense of flying for hire or reward other than instruction - for example, cargo or passenger flights. I have heard tell of Cessan Caravans flying cargo around the UK, but they are apparently registered in Sweden or somewhere else. I suppose there's perhaps an implied understanding of the risks of s/e IFR flight when under instruction, because your instructor says "turn the light on at 500' - if you don't like what you see turn it off" - but that's not addressing the legalities of the original poster's question.