Possibly. But the weird is that most of the time the values of the previous and the current values are correct. And the script works.
Naturally. The phenomenon is rare–occurs when Ignition’s subscription read of those registers falls on the same moment the count is updating in the PLC, and the low word rolls over in the middle of the 32-bit read.
Now already it makes more sense to me. Many thanks for your time and help, pturmel.