Yes- have taken MATCH off and its still the same... im along the lines of thinking as yourself.. relays work mechanically when i test them with my finger but it maybe that during operation, its just not pulling in enough.
The other problem i have is that the switch stack for Game Over etc is on a swing frame and its a real pain to get to the bottom leaf switches.
Dont have a Last Ball relay on this... 5th ball is registered by switch in the trough