The generic content have a different purpose to facilitate shared content in versions 4+. The best solution would be to migrate your legacy content blocks to either a dynamic module or to lists. You can find the Lists API here:Lists
. Should you decide to go with the dynamic module, you can create a very simple module and use the generated code snipped to create the items from your old content blocks.
Do you want to have your say in the Sitefinity development roadmap? Do you want to know when a feature you requested is added or when a bug fixed? Explore the Telerik Public Issue Tracking
system and vote to affect the priority of the items