This is intended to be used with DSfix. After installing DSfix...

In DSfix.ini, find this line:

dinput8dllWrapper none

Make it look like this line:

dinput8dllWrapper dsmfix.dll

Then, unzip dsmfix08.zip; place all dsmfix* files in the DATA directory (~Program FilesSteamsteamappscommonDark Souls Prepare to Die EditionDATA).

Finally, open dsmfixgui.exe and make the desired adjustments (mouse over an option for relevant tooltips); or, edit dsmfix.ini by hand.

For additional information, please see http://www.cs.wisc.edu/~petska