Keyboard not working / Diodes

[mx-ws]

Hi,
first of all, thanks for all the work!
I was following the guide and finally finished wiring everything together. I then flashed the firmware using https://github.com/flyck/ergodox-firmware as referenced in the guide. But the keyboard does not seem to work. I am not an expert in either soldering or teensy stuff, so if it looks like I'm just missing same basics, feel free to just point me to the right resources. I also realize this project should not be viewed as active, I just did not know a better place to ask. Here are some things I can say:

1. I noticed I am not using the diodes mentioned here: Wiritng Diode parts #67. A lot of time has passed since I bought the diodes I am using, so I don't remember my reasons. Could that be the problem and might it be worth a try, to buy the other diodes and replace them?
2. I successfully flashed other programs to the teensy, your usual hello world programs, from arduino as well as an example c program. Something curious I noticed is that the internal led will only light up if I disconnect PD6 (I only noticed because I did not solder this one well :D) Is that expected or could that point to the underlying problem?
3. I am able to light the three external leds, at least with arduino.

Any help appreciated =)