I'm on Windows 7 Ultimate x32 version.
After that I've observed strange thumbnail behavior for certain type of views in Windows Explorer. Please check the following screenshots :
For the file-type-view in windows explorer in the mode of "List" and "Small Icons", it must show the PDF-Xchange View Icon as default (As I have observed in previous version) but it shows some broken ICONS
Screenshot - 1 (problem)

Then, again with all other remaining types of file-type-view in windows explorer(large, medium, details, tiles etc..), PDF files shows its exact thumbnails.
Screenshot - 2 (no problems)

What's gone wrong with the first screenshot of file-type-view in windows explorer?