It is 1.0B released by Obsidian. Use the auto-updater or click the sticky "Kotor2 Patch" at the top of the Technical Section
It creates one Game-stopping bug (you can find a fix for it at the site of Team Gizka, see sticky in General) and several other smaller bugs, which you might not even notice if you aren't a fervent gamer...
And IF you wanted to delete the 1.0B if it goes wrong all you need to do is Re-Install Kotor2...