The house closed as part of the Scottish Costume Museum in 2013 and sat empty until it was officially handed over to local trustees last July.
The Lodge is the first part of the project to be completed and was officially opened by South Scotland list MSP Emma H arper.
The Cloverglen Centre provides essential services to assist persons with learning difficulties or mental health from the age of 16 upwards, having been founded by Eric Bridgwood in 2003.
Ms Harper said: “It was great to officially open the Cloverglen Centre at Shambellie House.
“ Over the last year the staff, volunteers and service users of Cloverglen have been working hard to redevelop the Shambellie Lodge as a base for Cloverglen Support Services which will provide training and support to more than 40 vulnerable young adults.
"Part of the training will include looking after the grounds, the young people have already started to learn gardening and there are plans to grow produce and plant trees – it is really exciting and encouraging to see.
“The redevelopment of the building at the entrance to Shambellie is an excellent example of reclaiming a vacant, abandoned, almost derelict building and transforming it to help deliver something very worthwhile.
“I look forward to continuing to work with Eric and all involved to see this project flourish and thank everyone – both at Cloverglen and the Shambellie House Trust – for everything they have done to transform the building and its fantastic grounds into a useful community asset.”
Eric and the young adults from Cloverglen have been an integral part of Shambellie for the past year.
He said: “Our young people love the scope of opportunities that we have had since coming to Shambellie.
"Their skills in managing the gardens, planting trees and flowers, and keeping the inside of the house neat and tidy while learning how to cook has been tremendous.
"We are grateful for the support of the trustees and the local community.”
John Stewart, vice-chairman of Shambellie House Trust welcomed everyone to the opening.
He said: “The Trust are very lucky to enjoy the company of these young people at Shambellie.
"We are learning a lot from each other and are looking forward to continuing our partnership with our young service users into the future”.
Shambellie House Trust was set up in 2015 to identify a new use fo r the building and to save it for the community, with the decision made to develop it as a creative hub.
The current scheme involves limited alterations and repairs to the House its elf, with work ongoing and it is due to open in April.
Cloverglen’s young people will be among the first to attend courses being offered at Shambellie in April and May.
Ann Hill will be teaching them to make cushions for their new accommodation during the ‘Quilt Fling’ festival which runs from May 19-29 at Shambellie House.
Further information on all the classes is available by visiting www.shambelliehouse.org