Are you guys both on Windows? I noticed that the Windows timeout values are defined much longer and I wonder if this is related. For Linux the timeout is 200mS but WIN32 is 999 mS. Note that I do all my testing on Linux and libusb could behave differently here.

Today I've been trying to verify the Fan Control FET circuit so that the board can be finalized. So far it will only work at 100% duty cycle. I've tried different things but always partial duty cycles cause immediate restart/shutdown. I added a resistor from the PIC output to GND to ensure the FET gate drops to GND when off, but no better. I just have a generic cheapo 3 pin fan and usually they can be controlled with PWM, according to my reading online, but perhaps some are different. (Note I'm not talking about PWM control in the fan like 4 pin fans, but just switching the 12V line with PWM.) I based my circuit off another well known working one so this is odd. I'll keep working on it.