Hello @Poley ,
I've seen that error before but I was unable to solve it because I cannot reproduce it on my end.
Regarding reading the UID, the other way s to use Data Read Mem block and type the direct address of the registers. Please see the attached example.
For the second request, restarting the MCU there are basically two ways. One of them is to use the watchdog, the other is to use the AIRCR register of the ARM Core. I tried the last one, and if you press the SW4 this should reset the MCU. Please see the attached exmaple. Also, the count variable is incremented every step time so once you press the button the value starts again from 0.
Hope this helps,
Marius