Mouse Pick Issues

I thought I had the quirky mouse pick action all figured out, but now it's back to laugh in my face. >.<

What should the checklist be to make sure that I am able to use the mouse pick in a 2D game using an orthographic correctly?

I'm using it fine in one level, but I see no difference between this level setup and the last, yet this level refuses to get a V3 from the mouse pick.

To clarify:
In the level it works I had to create an invisible plane right in front of the camera.

In this next...

Mouse Pick Issues