With no 3D floors this appears to be ok, but there are so many places where colormaps are being set in the software renderer that I cannot guarantee that I got all of them correct. This will need some testing.
This has increasingly become an obstacle with the hardware renderer, so now the values are being stored as plain data in the sector, with the software renderer getting the actual color tables when needed. While this is a bit slower than storing the pregenerated colormap, in realistic situations the added time is mostly negligible in the microseconds range.
(Is there anyway to tone down GCC's warning level? It outputs too many false positives for potentially uninitialized variables in which the genuine errors get drowned.)