I did grab a copy of Putty. But, there does not seem to be anything that you can do with it. It says, hold in the reset button until flashes slowly, but never does seem to get there. We tried to reset it there in place - which did not work. A copy of BitKinex. 5 and 5 Ghz connections and was fine. However, I decided to run with the stock or ASUS' firmware with the initial rollout and was working fine.
Tan Your Own Hide
Have an ASUS RT-AC66R - we had set it up for our church and was working flawlessly. I said that I would bring it home and still cannot get to it to re-flash/reset/hard reset/etc. I also had played with it initially and setup DD-WRT on it with no issue.
Networking ASUS RT AC66R hard reset Super User
We had set it with the 7. I even grabbed the Utility from Asus. Just cannot get there.