Also dripping oil from the engine carter.
Think you might have mistyped something there, would be helpful to know where the oil was dripping from
If you saw oil returning into the tank at presumably low revs and cold oil I think your filter should be fine provided you fitted an element recommended, I use the filter for a Citrion 2CV, these have little flow resistance you can easily blow through them.
other suggestion would be that you have the oil flow through the filter in the right direction, should be arrows on the filter head to show oil flow.
I've run a filter for many years now and oil flow is no problem, the capacity of filter elements are designed to pass oil flow from bigger engines than our As (well 2CV apart) so it should be no problem