Sorry, didn't see the topic until now.
The only information I found about it:
MSDN: Enumerating Keywords
MSDN: Using Registry Values to Enable and Disable Task Offloading
Seems to be about checksum calculation offloading; no idea why a rootkit should hide that; but registry paths are quite long and the shorter one just one character over 128; with two bytes per character that would be just over 256, a magical border that shouldn't have any effect here though. Overlength is a hidding trick, but not at this border - I just tested that both the registry supports keys of more length, and RootAlyzer as well.
You can see these two registry values through regedit.exe ?