The Gruntles, directed by Charlie Allen and Carey Thring, was chosen from hundreds of international entries from learning disabled film enthusiasts and screened at the Oska Bright Film Festival in Brighton.
The film has since been showing all through January in a pop-up cinema at the SOLD charity shop in Shoreham High Street.
Thanks to the tremendous response from customers, The Gruntles has now been released as a DVD to raise money for the charity, Shoreham Opportunities for Learning Disabilities.
Carolyn Shrosbee, founder, said: "We wanted to make a film in the shop and include the trainees. We were delighted when from hundreds of international entries, our little film was shortlisted to be shown at the three-day festival.
"Many professionals volunteered their time to make it happen, from the directors, lighting and sound technicians through to someone lending us their yacht for one of the scenes.
"Plus, local businesses Mitchinson Macken and Godspeed Courier financially supported us, so it really was a great team effort."
Written by Carey, the film starred Charlie Nicholson, Ellis Ashe, Jack Cameron Bruce, Sophie Boiling and Emily Skipp as the five members of the Gruntles family, who run a shop.
Charlie said: "It was good to do something we have never done before. They were brilliant with us."
Ellis said: "I really enjoyed it. It was worth it."
Sophie said: "It an experience. It was quite hard."
The moral of the story is that the Gruntles would do better if they learned to be more cheerful and welcoming.
Carolyn said the trainees are a jolly lot, so it was quite hard for them to act being glum and stop themselves from smiling.
The DVD is now for sale in the shop for a suggested donation of Â£5. It will also be available at a special free screening at the Duke of Wellington, in Brighton Road, Shoreham, on Tuesday, February 13, at 8pm.