How to add a limitation area

How to add a limit area to a water overlay manually:

Add an Area to the project. This will be the limit area.
Draw the limit area of the part of the 3D world you want to calculate with a water overlay.
Add an Attribute to the created Area, with the limit area attribute name and a value above 0.
Open the Water overlay wizard and in step 1, choose for Calculation area the option Limit to specified areas.
In the wizard an extra step will be added in where you will see that your created area is selected.
Continue with the wizard.

Notes

It is also possible to add a different attribute name for the limitation area, but with a value above 0. In that case, in the extra step in the wizard, choose for the option Select existing limitation areas based on attribute and select the custom attribute name of your limitation area.
It is also possible to import a limitation area. In that case, select in the extra step in the wizard the option Import limitation areas (start Geo data wizard) and proceed with the Geo data wizard.