I have converted the file successfully to the palette in palette.pcx. But when I tried to add a different terrain I found out the hard way why the palette had that many colours.
The cool elevations were using recolouring and shading algoriths that simply took the next colour in the palette. So, if you had yellows directly follow the greens, greens would appear until a certain altitude and then the yellows would take over. Very annoying.:-)