Nova Zembla is an island off the northernmost part of Russia, in the arctic regions. I think it has a colloquial meaning of "the end of the world" -- like Siberia. So the rose is very hardy. It is a rugosa hybrid and has beautiful blush (whitish pink) flowers, something like New Dawn, and with a heavenly clove-like scent, inherited from its rugosa parent. It is a sport of Conrad F. Meyer which is slightly darker pink. There used to be several specimens of it in the old Brooklyn Botanic Rose Garden, pruned to within an inch of their lives. To say it is a climber is a pleasant fiction. The truth is less attractive, for Nova Zembla and its parent have some severe drawbacks in their manner of growth. I used to grow this rose, so I know. 1) Even with excellent culture at the BBG, it was not all that floriferous. 2) It has tall stout canes, about the diameter of your fist, armed with thickly-set, truly vicious thorns from top to bottom. The foliage (as I grew it) was not especially attractive, profuse, nor healthy. 3) It blooms only at the very tippy tips of those tree-trunk-like canes. The head of the BBG rose garden in the 1980s was a devote of pruning and he kept his plants to five feet, and fairly presentable. Also, if you live in zone 4 it might not grow as tall. The scent is delicious. So why not try it. If you don't like it you can do what I did and get rid of it. I thought it was a hazard in my small city back yard, after accidentally cutting myself on it more than once. Some of the pics. on Helpmefind also reveal its manner of bloom. The attached one shows the thorns. Here is a link that might be useful: Nova Zembla showing thorns

Impossible to help much without more detailed information. Probably you'll have better information if you take a leaf to a local nursery for their opinion. If that's not possible, brown leaves when you bought/planted it? Photograph of the leaf underside? Location? Possible paint spatter? Etc. Etc.

It can mean any one of several things: 1) that you had a damaged root on that side when you planted it, or 2) that a burrowing animal or insect has chewed on a root on that side, or 3) that the roots on that side are dry, or 4) that you have a borer on that branch, or 5) that the roots on that side were too wet and it is getting root rot. Hopefully you roughed up the roots and spread them out when you planted it. If not, the roots will be or get root bound and problems will only get worse. It is best to give a good soaking watering about once a week in dry weather. I wait until I see morning wilting and then water, but don't water any more often than once in 7 days. Good Luck! Here is a link that might be useful: How to care for rhododendrons and azaleas.

The most likely explanation is that what you took to be flower buds in the fall were actually leaf buds. These would not yet be growing. Vegetative growth in rhododendrons takes place after the bloom period. Red flowered rhododendrons such as Nova Zembla are medium to late bloomers and would not yet have bloomed in Z6a unless you've experienced an unusually early spring. if there really were flower buds, they may still bloom or they may have aborted due to any number of possible causes. Be patient. Nova Zembla generally does not bloom or grow in Z6a until at least mid May.