Indiana Jones can have the same problem. The fix is to put either a metal bracket or 3D printed shape to make the area smaller and guarantee hits on the switch/eddy.

From what I've seen of the Alien playfield I'm not sure what would fit the bill, but as an example here's what I've done on my Indy to make sure the outlane switch never misses.

It's like a 3D printed boulder, normally put elsewhere on the game, but it fit perfectly here to gobble up the space the ball would bounce into when missing the outlane switch.

Looking at the geometry on Alien it would need a much different sort of shape than how I fixed it on Indy. Maybe something the starts flat against the metal guide and makes a curve to gobble up the space where the Eddy doesn't pick up the ball...

Anyways just trying to throw some ideas out there, the game looks super cool!

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