After coming back to this after a while, I discovered this page which solved it: https://help.ubuntu.com/community/Voodoo3doesnotdo3d Basically, you have to install libglade3 and then create an Xorg.conf (recent Ubuntus do not have one by default) to prevent anything else other than 16bpp and nothing larger than a mode of 1024x768. Now, I'm playing Total Annihilation like the old days, on hardware that's almost as old as the game :-)
