HoMM3 HD 4.100 RC4
+ Now, after installing the full version (4.100 RC4 and higher) on top of the old one, it is possible to revert.
When reverting from 4.100 RC4 to 4.0 RC33, the game becomes unplayable. When creating a map, there is no option to select a template or set roads; the timer does not work (or is simply not displayed) in the game; the interface shows 5 heroes instead of the usual eight. It is not possible to test anything else, as the game crashes when opening the tavern.
In 4.100 RC4, it is impossible to open a hero's backpack during another player's turn.