After installation HitFilm will start in demo mode. You can try out all the features but will be restricted to a 30 second export to YouTube.
If you have purchased HitFilm you can activate it immediately to use all of its features.
When you start the software choose Activate from the welcome screen.
Follow the on-screen instructions to activate your software. If it's the first time you have activated the software your serial code will be registered to your account at HitFilm.com.
You can also activate by going to the File menu, choosing Options and using the Activation settings.
Installing on another computer
The HitFilm 4 Pro license allows up to 3 concurrent activations.
If you exceed your number of activations your earliest activation will be deactivated and return to demo mode.
You can transfer to a new machine and reinstall as many times as you want, so there's no need to worry about losing your purchased software.