>>>
>>>"I will not charge for the services to implement the above described features. These features will be enabled with valid Program support."
>>
>>Nothing stopping them from complaining if these features vanish/are disabled when they cancel Program support.
>>Add "and will continue to work while..."
>
>If they want to complain, they can :)

If they don't via lawyer in front of a judge or mediator, no cost added to your side - but if they choose such an audience, the US way of lawyer compensation might cost you a bit - even if only for your represetation.