>2. Tried placing MMBusinessLayerGenerator.addin in other locations identified by Tools->Options->Add-In/Macros Security.
Where else did you try placing the addin?
C:\Documents and Settings\<current user>\Application Data\Microsoft\MSEnvShared\AddIns
C:\Documents and Settings\<current user>\My Documents\Visual Studio 2005\AddIns
Regards,
Fred Chateau