Hi,

What do I treat prof=0 event?

prof=0 means profile is zero, totals are not.
So you'll need to go to Edit->Meter Totals and interpolate profile between those 2 dates.
Or you can go to Tools->Audit Meter and choose the correct register.
Beware that interpolated profile does not work for Demand Tariffs (unless you read demand from a special register or capture it manually under Tools->Bulk Capture Manual Electricity Readings)