Hi moet,
When you first start the game it will say at the bottom of the screen Version 5.16 (474).
Just remember the install is in two parts,
After you download the patch, open the folder then first click on the big Red Star that says kharkov_patch 516e.
Start the game as normal and click on the "?" bottom right of the screen. This opens the installer. Click on "install" then find the folder "CORE_EN" (for the english version). Then in this folder click on "desc.addpack", then "Save and play".
And youre all done, enjoy.