If you want to have an better understanding of how the roof works there are some very good videos on tophydraulics.com They explain how the system works and how to diy trouble shoot as well. The company can also supply replacement hydraulic cylinders and hoses if you have an issue. The only negative side is they are based in the USA.
Look on the DIY section for videos.
There is also a company based in Chester called Hoodtech who can resolve softtop problems.