Guys,
Mystery solved.
All my fault, plus assistance from the H/W manufacturer ...
Seems that port0 MAC ended :0b and port1 ended :0a, so I basically had them labeled the wrong way around. PfBlockerNG was set up on the 'outside' port, hence what I was seeing.
Like I said - all my fault, but I'd still love to have a minute with the olympic class ^%$ head that designed it this way.
Hope someone else benefits from this experience.
Chip