There is a new WF Extensions beta that has been made available for download here. The new extensions fix the following issues noted from the above link.
- Showing of interface types that are nested while trying to select interfaces
- Being able to select overloaded methods within the "CallExternalMethodActivity"
- Showing of interface types that are nested while trying to select interfaces.
- Being able to run more than one workflow within the same VS Project.
- Error notification when trying to detach the debugger from a process.
Checkout the requirements before trying to install!