Try this: http://www.microsoft.com/en-us/download/details.aspx?id=35 it might work better than the DirectX setup file.
did u use google chrome to downlod the game?if u did try downloading it with ie or firefox.google chrome tends to corrupt files while transfering.
Again this is the best option for the missing dll file
First, its DLL missing.. you need to re-download EPW Client.. and Second maybe its your directx is corrupted or didn't full installed
Hmm, this is very odd.. Try to disable your anti-virus and any other security software then try to install it again.