On the AddDetails page there is a 'picker' to select the desired value. How can i change the text('Cancel' and 'Done')? I cant find any string items where i can change the values.
Unfortunately, that is system provided control and cannot be altered. This is not controlled by the QuickReport template. However, if you would like you can update the combobox control to the latest QtQuick.Controls 2.1
ComboBox QML Type | Qt Quick Controls 2 5.9
Currently, it is using the combobox from QtQuick.Controls 1.x. This will provide you a new look and feel of the combobox.