Where is the tool "Loft Rectangle to Circle" in CONNECT?
The tool "Loft Rectangle to Circle" can be found under Workflow Modeling > Surfaces > Create Surfaces > Loft > Loft Transition
Other option how to find this tool is to use following key-in: loft blocktocircle
https://docs.bentley.com/LiveContent/web/MicroStation%20Help-v15/en/LoftBlockToCircle.html