Fresh cranberries will give less character than would expect compared to other berries. Cranberries just don't break down either by freezing or by soaking in beer/cider. Concentrate or good quality 100% juice will gie you a lot more control over your end result.
If you do choose to use berries, put them through 2 freeze/thaw cycles and crush them after each thaw to help them break up better. I am always amazed at how well my berries hold up after a hard frost, and even after a year in the freezer they are pretty firm after thawing (just ask my ducks lol).