From Dekho 3.2.2 onwards, custom tools will need to be recompiled against the Esri AcrGIS API for Flex 2.4 library if required. See the Custom Tools section in the Version 3.2 section of this documentation for further details if upgrading from Dekho 3.1.x to 3.2.2.
The Dekho Simulator project has been updated to include the same Skin classes as the main gui of Dekho. By using these skin classes your can make the forms of your custom tools look the same as the forms in Dekho. All the sample tools have been updated to use the Skin classes and can be used as a reference.
Two new sample custom tools have been added: a convex hull geometry service tool and a multimedia tool that plays YouTube videos with in an InfoSymbol renderer.