If not started, please start the print service. You can do this from the Android settings menu. Just choose Printers/zenofx.com PrintBot. After an update, it may be necessary to stop and start the print service or even reboot your device.
Just start your favourite viewer app and choose the "Print" menu or use PrintBot's integrated file browser.
Basically no. PrintBot accesses your printer directly, so it will only work when your Android device is in the same network as the printer (usually by Wi-Fi). If you really know what your're doing, you can disable the WiFi check using "Settings/Advanced". Use at your own risk!
In many cases, all protocols (LPR, IPP and Raw) will work.
In many cases, putting in the host name of your printer won't work, as your Android device probably is not capable of resolving the names in your local network. So putting in the IP address of your printer (or print server) is the safest solution. If your print server is running on a non-standard port, an IP:port syntax is also possible.
The current version has an additional auto scan feature.
Use the "Raw" protocol and "fritz.box" as the host name.
Windows 7 comes with LPR support as a "Windows feature". This will work if you
Mac OS X already comes with LPR support. This will work if you
PrintBot is based on Linux printer drivers. Unfortunately, not all Linux drivers are equal in quality compared to the Windows ones.