Between version 1.6.8 and the current version, something seems to have broke with the pin interrupts on my Zero compatible Tau boards, according to one person using them.
I haven't changed the board definition at all, so something has changed at some point which caused them to break. They work fine when you define the interrupt by physical pin, but not digital pin.
I'm not even sure if this is something which is defined within the board files actually. It may be something in the SAMD libraries was changed.
This is all the information I have on the issue:
The "attachInterrupt(digitalPinTo Interrupt,..." no longer works... Use the actual pin number and you are in business... "attachInterrupt(physicalPinTo Interrupt...." works flawlessly.