I noticed that the + key from the numpad always reset back to Camera Zoom In when I entered the game. I submitted a ticket, the GM asked me to speak to technical support, which I did, and they gave me a quick and straightforward response: some keys reset to the default options (whether you like it or not). It's part of the design.
May I ask what is the reason for this? I can't really think of why you would want a key to reset back, when you already give us the option to change it in the first place.