LondonFlyer's comment is very valid (and thanks for the EDDI chart - managed to get there before they closed it
). The skills the rating generates are far more important than the rating itself IMHO. Those of us whose licences are not held on the UK register have no chance of such a rating, yet I and many of my friends undertake regular instrument-based flights with instructors and safety pilots and informal ground-school to prepare ourselves for the conditions the IMCR covers.
I suspect EASA will come to some arrangement (perhaps grandfather-rights, perhaps some "fudge"), but either way don't be put off the training.