Here be dragons.
From the department of "because it was there", following in the tradition of "knocking the bastard off".
Executive Summary - You can use Windows 10 IoT Core and Feeder to read your Snapper card.
Requirements:
Target:
Raspberry Pi 2 B with Windows 10 IoT Core installed
Snapper Feeder
Snapper Card
Mouse, Keyboard and HDMI monitor
Network connection to build host and internet.
Build Host:
Window 10 desktop/laptop with Visual Studio 2015
Procedure:
Setup the WinUSB driver according to https://sourceforge.net/p/myfeeder/wiki/win8usb/
Read https://sourceforge.net/p/myfeeder/wiki/win10iot/
Grab source from either
svn checkout svn://svn.code.sf.net/p/myfeeder/code/trunk/win10iot MyFeeder
or a snapshot from
http://sourceforge.net/projects/myfeeder/files/Win32/MyFeeder-vs2015-r20.zip
Open MyFeeder.sln with Visual Studio 2015
Build it for Debug/ARM.
Enter the IP address and select no authentication under Remote Machine.
Press F5 to debug on your Pi.
End state:
The program running on the Pi should recognize the Feeder and let you read the balance from your card.