I have found that by everyday starting the rotator fresh (a web switch turns off both it's 12V for motor and also the powered usb hub it's connected through).. it is very robust!! I have had now several completely unattended day/night ACP imaging sessions with occasional cloud closures with complete success. Leaving the rotator on all the time it is very unlikely to have 3 good nights in a row.
The shutter firmware (0.5.3.2) has a major limitation.. Say it is closed and closed switch knows about it. If the battery is unplugged so the shutter Arduino also goes off there is a problem. When the battery is reconnected after the shutter boots up it is not accessible until the rocker switch is used to open a crack then close. After that it is ready to go.
If the shutter firmware initialized to recognized "closed" when at switch some really simple like a $12 digital chicken coop timer could be setup so that the shutter also starts fresh each day! I can imagine setting such a timer for turning it off at ~10am and back on again ~4pm..
IMHO this is a major bug we need to address because it would remove a significant limitation and also greatly improve overall robustness plus save needless hours of on-time with the shutter arduino. The rotator is quite happy and ready to go on restart and the shutter should be as well.