Latest findings :-)
Did you ever receive "Unknown Error" (love these descriptive messages)when trying to view version history on the item? I did. As it turned out it was directly related to the issue I had with viewing properties of an item. Anytime I've opened "View Properties" it would redirect me to the portal home page. Once the Dispform.aspx page was fixed, I had no issues browsing to the version history.
Because my priority was to resolve version issue before display properties redirection, all research was fruitless, If you are doing the same, take a look at your view properties page first.
Enjoy