go to the brick you want to be effected
wrench it
name it
go back to the events
where is says [self]
[player]
[client]
go to where it says [named brick]
select it
fill out the event you want!
You failed at being helpful.
Here is what you do.
Where you want the projectile to spawn from, lay a brick, name it 'spawnProjectile1', then turn collision and rendering off.
Go to where you want the button to trigger the projectile to be, place it, then call it 'projectile1Trigger'.
On events on brick 'projectile1Trigger', do these events:
onActivate>NAMED BRICK[spawnProjectile1]>spawnProjectile>[whatever you want]
Hope that helps.