NFC not picked up by phone

That's odd - as soon as you do reset() or save() on the Puck it'll remove the built-in NFC URL, but NRF.nfcURL("http://espruino.com"); should work.

You could try lighting up an LED based on the NFCon and NFCoff events? http://www.espruino.com/Reference#l_NRF_­NFCoff

You could also try comparing the Puck PCBs to see if something is amiss - on the PCB at the bottom-right corner of the bluetooth module it says D7. To the right of that there should be two white components. Those are the tuning capacitors for NFC - the only components that are part of it - so if one of them looks like it has a problem that could cause it?