Great enhancements with 1.5!
But found some filter issues after testing:
1) If filter doesn't find records, then the "activity logs are empty" message is displayed instead of "no matching records found". Only re-selecting the wp-activity menu option refreshes the filter, while one should be able to select a new filter from the same screen.
2) Filter SORTING by User doesn't seem to work
3) Pressing "Exporting filtered data" button results in 404 page
4) "There is currently xx rows in database" info on Events Logging and Feeding screen is influenced by filter used on Activity screen. This should not be the case.