Why won't my Help work? (same download as main package.)

I have installed LibreOffice 3.5.5.3 (Build ID: 7122e39-92ed229-498d286-15e43b4-d70da21) on a PC running Windows 7 Home Premium (64-bit). I downloaded the main package and installed it. A few(?) days later I downloaded the Help package and installed it. Help does not work - I get taken to the online Help page. What’s the best way to debug this and get my installed Help to work? Is it possible the online Help package changed versions before my delayed download and will not work with an earlier version? How can I check the version of Help I downloaded? If my versions are not matched, what’s the most reliable way to get them to match without polluting my PC with old files and registry keys?

What is your native language? Do you downloaded Help package for this language? In the setting (Tools - Options - Language Settings - Language of User Interface) of the interface of office suite the set to that language?