I am still having this problem occasionally but I am traveling a lot so I did not have time yet to call and see what support has to offer. In my case the unit itself always responds to the Web interface but the PLM controller dies.
Yesterday I upgraded to V1.56 and then the unit froze again. Only one of my timers executed, the others probably wanted to but when I logged onto the unit it said the PLM controller was not responding.
Question: Can the software reset the PLM controller like it had been unplugged? Could you add a PLM heartbeat every 5 minutes or so and reset the damn thing when it dies? If that’s currently not an option I would highly recommend to change the hardware design to enable this functionality and to provide us early adopters with an upgrade option, for a nominal fee.