yes we did vienna xmas markets as well. its quite easy. the biggest tips would be not to boil it. gentle simmer. any more and it destroys the alcohol and makes it bitter. same with adding too much of the orange "pith" the juice is good, and the gentle rind bits... just not too much of the bitter pith parts. The biggest no no... is to boil it. other wise its kind of hard to mess up. However i have never done ones with red berry or apple... only a gentel red wine like a merlot or even cab sav.