After reading through the thread I would say that the problem is with the trigger not breaking the opto sensor correctly. Seeing as the old trigger works fine, and when you undid the set screw and gave trigger more play (enough to break the beam). The ramping side I think is just a red herring.
One thing you could try to test this, is to stick a piece of black insultating tape to the bit of the trigger the breaks the beam to make it a bit bigger.
The other thing is the Board normally has a bit of play as to where it sits. try undoing the screws a little and move it close to the trigger or up if you can and then retighten them.
If neither works then thats the problem If not back to the drawing board
One thing you could try to test this, is to stick a piece of black insultating tape to the bit of the trigger the breaks the beam to make it a bit bigger.
The other thing is the Board normally has a bit of play as to where it sits. try undoing the screws a little and move it close to the trigger or up if you can and then retighten them.
If neither works then thats the problem If not back to the drawing board