When I try to install Helm, I get to the screen where I enter my licence key, but upon entering the key it just sits there - even if I uncheck the Activate Now box.
1.) Check, double-check and triple-check that you are typing in the key correctly.
2.) As per the Pre-Install Guide, make sure that you have got MS XML 4.0 SP2 installed.
3.) Make sure you have an internet connection - without one, Helm cannot contact the licencing server to check the licence.
4.) If none of the above works, raise a support ticket with your licence provider.