Sorry if I'm missing something terribly obvious, but is there specific documentation for the Splunk for Windows app downloadable here:
Splunk for Windows is a simple application intended for reference purposes. It does not have any additional documentation. If you need more information about using Splunk to monitor Windows data, you should refer to the main product documentation, particularly the "Get Windows data" sections of the Getting Data In manual (for example, http://www.splunk.com/base/Documentation/latest/Data/ConsiderationsfordecidinghowtomonitorWindowsdat...).
Substantial additional content for Windows administrators using Splunk is now available! http://docs.splunk.com/Documentation/Splunk/latest/Admin/IntroductionforWindowsadmins