The main documentation is here.
https://github.com/TomWhitwell/RadioMusic/wiki
We suggest approaching it in this order:
1) Start by preparing the Teensy
https://github.com/TomWhitwell/RadioMusic/wiki/Preparing-the-Teensy-3.1
Hex File (software to flash the Teensy) - https://github.com/TomWhitwell/RadioMusic/blob/master/Collateral/hex%20files/Latest/RadioMusic1_1.cpp.hex
2) Build document here
https://github.com/TomWhitwell/RadioMusic/wiki/Building-the-Radio-Music-module
3) Prepping SD card here
https://github.com/TomWhitwell/RadioMusic/wiki/SD-Card%3A-Format-%26-File-Structure
4) Testing and Calibration here
https://github.com/TomWhitwell/RadioMusic/wiki/Testing-and-calibrating-the-Radio-Music-module
5) Troubleshooting and FAQ
https://github.com/TomWhitwell/RadioMusic/wiki/Troubleshooting-the-Radio-Music-module