If you already have the tools installed, you can update them by simply running the Cadimage Installer.
Login into the Cadimage Installer and then click on the Update button in the upper row of the interface. You will then see a list of updates that are available for you.
Similarly to the install process, you can then press the Update button to install any updates that you want, or hit the Update All button to install them all in one go.
Once the process is complete, just exit the installer by clicking the Close button.