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You can set the depth test of a shader to only draw behind objects, or you can use the stencil buffer to mask specific things

You just move the shader file. You shouldn't be able to get any namespace errors, unless you accidentally moved scripts or the .dll

Odd. It could be that box projection simply isn't supported on UWP. I would try disabling it for UWP specifically

There's unfortunately no way to control this, as the inspector will either be overridden by ASE or SF. It can't detect which type of shader it is to branch before it's too late

Yeah, we've just moved office, and have a pretty tight schedule with an internal deadline coming up for Budget Cuts :)

I've been super busy with other work as of late, which is why it has taken me quite long to solve this! I apologize for the delay, but I will look into this next week

Make sure you're logged in to the same account you bought the license with. If it still doesn't work, you'll have to ask Unity for help, as the asset store download systems are out of my control

It's likely because it's used in the refraction input in this case. It should work though, so it's a bug

What happens if you change the Screen Pos mode from Tiled to Scene UVs?