The TortoiseHg that ships with KilnTools is no different from that you’d download directly from the TortoiseHg project. We do bundle a few extra extensions with it, and if you lack a Mercurial.ini file, we will set up one for you, but otherwise, there is (currently) no difference.
There is one extension you do likely want to enable, called
kilnauth. This extension will use your Kiln cookies to log into Kiln, meaning that you only need to type your login and password once per Kiln installation that you access. To add it, add the line