Your first encounter with an Orval can be "different". I first had an Orval in Amsterdam in 2001 and was not impressed. I think it was the "horse" smell that put me off. I waited another 3 or 4 years before forcing another attempt. This time, I appreciated it much better. I agree it must not be too cold. I now really like this beer and consider it a unique and very enjoyable brew. I have also noted it can vary quite a bit between batches. I bought a case of it from realbeers.ie when it was their "beer of the month" intending to see how some of them might age. Unfortunately, my plan was doomed to fail; I couldn't stop drinking them!
Give this one another chance!