The 0.4.0.6 version is for systems without dx11 support as it is the last one utilizing dx9. It also has less features than the current version and is less optimized. So unless your system can't handle dx11 you should use the newer version.
Yes I do, and I found out that it isn't a good idea, since it caused my pc to "Blue Screen Of Death", so I found out my pc uses DX11
what? Just because your PC has DX11 doesnt mean your PC will BSOD on DX9 unless you have major issues with your PC that should be rectified.