I get the d3dx10_34.dll cannot be found if I try to start in dx10 but cannot seem to find a fix.
I have q6600 no OC
4 GB DDR2
Vista Premium 64
so all seems like it should run in DX10 but I get the error everytime but if I run in dx9 there are no issues. I just updated the drivers last week so I don't think that is it and I have installed all updates in Vista.
If you haven't got it solved by now, this might work.
The file you mentioned is a component of DX10. Just reinstall DX, using the Crysis installation DVD. Use the Explorers search function and look for a folder called directx. There you should find the setup.