Excellent find, thanks for the report.
Curiously, this does not appear to be the result of a code change in KiX itself, but due to some change in the VS2010 compile/build run. (Because if I build the 4.61 code, the same issue appears...) Maybe a change in the runtime libraries, maybe the optimization.

Also strange is the fact that everything else appears to work just fine, including automation of other COM objects..

This will require some investigation, and as I'll be busy elsewhere the next weeks, I'm afraid it may take a while to fix.

Ruud