2.07 is supposed to support DX9 hardware
X1800 is in the grey zone though - ATI couldn't be bothered with releasing an OpenGL 2.1 driver for it and we (TDM) didn't care about 2.0/2.1 compatibility
In our defense, we don't have any DX9 hardware to test on
And then, TDM does not offer an easy or obvious way for installing a previous version. If it was that simple, we would have just offered OP to click that button and be done with it.
Expect a lot more threads like this when 2.08 rolls out.