Modeler - Process migration

Which is the best way to migrate process models in 6.5 environment to designer 7.0

The designer documentation suggests a direct export/import , which in my opinion may not be that straightforward and might require more customization , post migration to make it work.

Is taking export of models in BPEL and importing them to designer makes sense?

There was a option in Modeler 6.5 to make the process model be available