I noticed a log.txt file in there next to the cache directory. It looks like this:

@Header SceReaderLog
@Version 1.0
2008-04-30T11:48:31-07:00,Information,Count: 1
2008-04-30T11:48:31-07:00,Information,Arg: C:\Users\jdavis\AppData\Local\Apps\2.0\X7NV95L0.T5E\RLV22R41.MKX\msdn..tion_c3bce3770c238a49_0000.0005_6dc707e38b72a451\MsdnReader.exe
2008-04-30T11:48:37-07:00,Information,DataManager: Load from local cache started
2008-04-30T11:48:37-07:00,Information,ViewManager: Navigated to path: cat.xml/Web
2008-04-30T11:48:37-07:00,Information,DataManager: Load from local cache completed
2008-04-30T11:48:38-07:00,Error,DataFeedSource: Unable to create ImageSource from data stream. URI: /msdnmag/issues/07/09/ScriptManager/fig04.gif, Error: No imaging component suitable to complete this operation was found.
2008-04-30T11:48:38-07:00,Error,DataFeedSource: Unable to create ImageSource from data stream. URI: /msdnmag/issues/08/01/ExtremeASPNET/fig08.gif, Error: No imaging component suitable to complete this operation was found.
2008-04-30T11:48:38-07:00,Error,DataFeedSource: Unable to create ImageSource from data stream. URI: /msdnmag/issues/07/08/CuttingEdge/fig02.gif, Error: No imaging component suitable to complete this operation was found.
2008-04-30T11:48:38-07:00,Error,DataFeedSource: Unable to create ImageSource from data stream. URI: /msdnmag/issues/08/01/CuttingEdge/fig02.gif, Error: No imaging component suitable to complete this operation was found.
2008-04-30T11:48:38-07:00,Error,DataFeedSource: Unable to create ImageSource from data stream. URI: /msdnmag/issues/07/12/CuttingEdge/fig05.gif, Error: No imaging component suitable to complete this operation was found.
2008-04-30T11:48:38-07:00,Error,DataFeedSource: Unable to create ImageSource from data stream. URI: /msdnmag/issues/07/05/Groove/fig01.gif, Error: No imaging component suitable to complete this operation was found.
2008-04-30T11:48:38-07:00,Error,DataFeedSource: Unable to create ImageSource from data stream. URI: /msdnmag/issues/07/07/CuttingEdge/fig02.gif, Error: No imaging component suitable to complete this operation was found.
2008-04-30T11:48:38-07:00,Error,DataFeedSource: Unable to create ImageSource from data stream. URI: /msdnmag/issues/07/04/ASPNET20/fig05.gif, Error: No imaging component suitable to complete this operation was found.
2008-04-30T11:48:38-07:00,Error,DataFeedSource: Unable to create ImageSource from data stream. URI: /msdnmag/issues/07/04/ASPNET20/fig05.gif, Error: No imaging component suitable to complete this operation was found.
2008-04-30T11:48:38-07:00,Error,DataFeedSource: Unable to create ImageSource from data stream. URI: /msdnmag/issues/07/12/ServiceStation/fig01.gif, Error: No imaging component suitable to complete this operation was found.
2008-04-30T11:48:38-07:00,Error,DataFeedSource: Unable to create ImageSource from data stream. URI: /msdnmag/issues/08/01/WickedCode/fig01.gif, Error: No imaging component suitable to complete this operation was found.
2008-04-30T11:48:38-07:00,Error,DataFeedSource: Unable to create ImageSource from data stream. URI: /msdnmag/issues/07/08/ExtremeASPNET/fig01.gif, Error: No imaging component suitable to complete this operation was found.
2008-04-30T11:48:38-07:00,Error,DataFeedSource: Unable to create ImageSource from data stream. URI: /msdnmag/issues/07/09/CuttingEdge/fig07.gif, Error: No imaging component suitable to complete this operation was found.
2008-04-30T11:48:39-07:00,Error,DataFeedSource: Unable to create ImageSource from data stream. URI: http://msdn.microsoft.com/msdnmag/issues/07/03/IIS7/fig02.gif, Error: No imaging component suitable to complete this operation was found.
2008-04-30T11:48:39-07:00,Error,DataFeedSource: Unable to create ImageSource from data stream. URI: http://msdn.microsoft.com/msdnmag/issues/07/06/Silverlight/fig08.gif, Error: No imaging component suitable to complete this operation was found.
2008-04-30T11:48:39-07:00,Error,DataFeedSource: Unable to create ImageSource from data stream. URI: http://msdn.microsoft.com/msdnmag/issues/07/05/JavaScript/fig03.gif, Error: No imaging component suitable to complete this operation was found.
2008-04-30T11:49:04-07:00,Information,ViewManager: Navigated to path: cat.xml/Web/http%3A%2F%2Fmsdn.microsoft.com%2Fmsdnmag%2Fissues%2F07%2F04%2FASPNET20
2008-04-30T11:49:04-07:00,Error,DataFeedSource: Unable to create XML document from data stream. URI: /msdnmag/issues/07/04/ASPNET20/Article.xml, Error: Unexpected XML declaration. The XML declaration must be the first node in the document, and no white space characters are allowed to appear before it. Line 3, position 3.

.. all the way down a few hundred lines.