Okay, so I tried the new version, and found this:
Everything's transparent. And I mean everything. The little specks are my dining room, bedrooms and noble's rooms. The black thing is the bottom of my chasm, 30 odd z-levels down from the tower the camera is beside, with the tower semi-visible.
Anti-aliasing not available with 16 samples. Choosing best.
Anti-aliasing: 4x MSAA
Shaders disabled
Vertical sync disabled
Anisotropic filtering level 16
Version 0.28.181.40d is supported
Version 28.181.40d11.win is supported
Version 28.181.40d13.win is supported
Version 28.181.40d14.win is supported
Version 28.181.40d11.win is supported
Version 0.28.181.40d detected
Reading map with size (12, 12, 40)
Reading material information...
Matgloss type 1 read. 230 total
Matgloss type 2 read. 26 total
Preparing to read map...
Reading blocks...
Creating Imposters...
FBO created (2048, 2048, depth_rbo)
RenderTexture 'ImposterRenderTexture0' created
RenderTexture 'ImposterRenderTexture1' created
ImposterCollection built -
Target size: 2048
Target count: 2
Mesh count: 64
FBO destroyed
Initialising geometry pager...
Creating geometry...
Transferring geometry to GPU...
Loading textures...
Generating shadow map...
Done
Also,
Again, the transparancy, but don't you think that's a little steep? It's only 8 z-levels.