Not sure if this helps, I have completed this and currently building another cleaner version. But ran into some of the same issues.
To calibrate:
you need to plug the teensy into the PC (This will power the teensy) (NOTE:This is after you have loaded the potv6 teensy file to the teensy) then take another usb cable plug it in from the DS4 usb port to the host shield. Wait like 20 seconds and unplug all USB cables. That's it, the host shield should be calibrated. There are no blinking lights. (Might be a good idea to add blicking lights though.)
After calabration:
Plug in the DS4 USB CABLE fromt he PS4 to the teensy. Then Plug in your edge+KBM+wired xbox controller to the host shield, or to do a quick test, just plug in just the wired xbox controller only. To turn on the DS4 board, press the XBOX logo button, which if wired correctly is like hitting the ps button on the DS4. (You no longer use the DS4 USB port)
The reason I used the xbox controller is becuase I could not get it to work with the PS3 controller, not sure if it works with the PS3 controller or if i did somthing wrong, but it never work with it.