The vast majority of people will have GPU's that support at least basic shaders (SM 1.1+), so the lighting and depth cueing will look better for most people. But first I'm going to get the fixed function render, which I've been showing so far, complete before worrying about putting shader support back in.
You can see the fixed-function depth cueing here:
[Before / After]


Another screenshot for fun:

All the basic rendering elements are in place, so the next step is to go through and fix bugs - such as occasional alignment issues with floors and walls. Once the rendering is robust I'll get the other projects rendering everything again - which should go much quicker since most of the engine work is done.

Finally once all the projects are properly rendering using the fixed function path, I'll add the shader path back in - with improved lighting and color map support - and then move on to getting the gameplay ready for the release.