The 7z archive (I have checked) contains all files from 11.07 with version 4053. So if you already have some files that was new in HE folder, probably they were partially updated by installer when you got message that something is in use, or what ever.
To see who is locking dll, you can do Find dll in the Process Explorer, when you get such message.
Maybe something wrong with installer, but I would only check this if I get same symptoms from other users. Otherwise I would think that some particular problems appear on your system.