Right now, on the original firmware, when using an AsicBoost pool, the miners behave very strange, and basically do not work. They keep on turning the fans down for a second and restarting (sorry, not sure if they are actually rebooting).
1. Nicehash or any other mining rental service is a terrible idea to use. Sure they pay you but it is a fraction of what they earn from your gear. Join a PPS pool - you will earn more.
2. I assume you are talking about Nicehash's AB pool? It sux big time to the point of needing the special driver that Canaan made to run their miners there along with NH having a dedicated AB connection address. The Avalons all work fine on non-rental pools and all pools these days will run AB if the miner can do it - no special driver or connection required.