Do you think this could be combined with the KADE firmware to make a skee-ball controller/encoder?
I don't see a stopper to add this to the KADE framework. At least as a selectable firmware it should be easy.
For my own cabinet, I made a composite device (2 Joysticks, 1 Keyboard, 1 Media Device, 1 LED-Wiz), based on the sources of the "AVR Atmega V-USB Mame Arcade Panel Controller" and the LWCloneU2 and run into problems with the original 'ledwiz.dll' and therefor created my own 'ledwiz.dll'. I don't know in detail about the KADE encoder(s) and how to combine it with LWCloneU2 but I think it should be possible to create a "skee-ball controller/encoder".
How are you licensing the source code?
All sourcecode and provided schematics that is created by me (*) is free, i.e. anyone can use it for whatever purpose.
The uC firmware is based on the LUFA framework, that states on the homepage:
"LUFA is free to use - even for commerical purposes, subject to the MIT license restrictions (see project documentation)"
(*) some sourcecode is derived work and so not fully covered by my *free* copyright.
In the provided *.zip file, this applies to the folowing files:
\win32\driver\include\ledwiz.h (this is a modified version of the interface header from the official LED-Wiz SDK)
\firmware\* (all files in this folder are based on an example of the LUFA framework concerning the USB stuff. The LED control is from me)