- The road type of the roundabout is always the same as the highest road type connected.
- Enter as Speed limit the highest maximum speed of the connected segments.
- A dead-end street (cul-de-sac) should not have a roundabout at the end (see above).
- If there is no road sign for a roundabout, don't use a roundabout.
- In some cases, a roundabout is not used even if there is a roundabout sign, to create the best possible instructions for the situation.
- Don't connect more than one same direction segment on to 1 junction of the roundabout
- Don't make connections within the roundabout. This lead to weird instructions, like "take exit zero", or no instructions at all.