Well, all I did was go through the installation to a fresh directory with all the highest graphical options checked. I would note, however, that some items in the game are not visible with the newer textures enabled. For example, for the first Wizard class quest for the Arcane Staff, the Enchanting Altar in Blackburrow was not visible at all (nor had its 3d collision been enabled). I had to install Titanium again to another directory in order to see it to complete the quest. I did not do anything fancy, did not modify any files whatsoever.
In case there are other variables involved, I'll post my specs:
Windows 7
AMD Athlon X2 2.4ghz
8600GTS
(other machine is same, running Windows XP)