I am having trouble getting an external FTDI like usb2serial light working with this custom Arduino project:
http://ministickers.nl/Media/schematics.png
As you can see, I included a capacitor of .1uF / 100nF 50V. What do I miss that is in the original Arduino's?
Of course I can and do use my ISP programmer, but especially for my students the FTDI board is more convenient.