This is a replacement blog-post, based on our developing understanding of the problem and users' experiences. It appears that the update that disrupts the operation of 'tree' controls in HBSMR v3 and v4 is Security Update MS12-060. Symptoms include inability to select items in a tree or, in the case of v3, an inability to add new MonTypes, Components etc. The problem relates to the version and registration of mscomctl.ocx

Microsoft has now published guidance on how to resolve this issue. Please see:

http://support.microsoft.com/kb/2748410