A few quick updates:

1. Please make sure to use the latest Quantum wallet/node. As of Oct. 11th, 2017 this is https://github.com/qtumproject/qtum/releases/tag/mainnet-ignition-v1.0.2 . You'll want to download the qtum-0.14.3-arm-linux-gnueabihf.tar.gz file.

2. Some people have mentioned having difficulties with Etcher on Windows (e.g. https://github.com/resin-io-modules/drivelist/issues/208). Windows users may want to look at using https://www.raspberrypi.org/documentation/installation/installing-images/windows.md instead.

3. If you're using Windows, the documentation at https://www.raspberrypi.org/documentation/remote-access/ssh/windows.md can be helpful for using PuTTY. If your wifi is set up correctly on your Raspberry Pi, the Host Name (to enter in PuTTY) should be raspberrypi.local.