Hasta La Motion!

I am trying to understand some basic stuff in terms of the linear work flow. I hope someone will have the answer to enlighten me.

I am having trouble understanding how to interpret 50% gray while working linear, this seems like a fundamental issue to me, but maybe I am wrong? Again enlightenment would be appreciated.

To explain my confusion I have a few images:

This first image is an 8bit render from a 3D application, as interpreted by After Effects in an 8 bit sRGB color space project. As expected 50% gray is visually, as expected, halfway between black and white.

This next image is a 32 bit render from a 3D application. This one is gamma corrected so that it will be interpreted properly by After Effects in 32 bit linear color space.

This last image is the 32 bit rendered image as interpreted by After Effects in a 32 bit linear space project. As you can see the grays are identical visually to the 8 bit image, but the values have changed. Why is this occurring? Is it a good/bad thing? What are the implications for compositing?

Thanks for reading or for answering any of these questions.