I've run into this issue:
Two layers containing firewall blade.
First one consists of just two rules, with second being cleanup pass-on to the second layer with no logging.
Second layer actually contains the rules that are expected to log the traffic.
But when the log for the rule in the second layer is viewed, it idicated that the rule two of the first layer is handling this traffic.
While in a sence it is true, it missrepresents the subsequent processing.
Excluding rule 2 from the log returns empty screen: