I know in the tutorial it says what data types are valid, but I cannot get it to recognise Double.
(but it does recognise Float instead, but won't allow decimal places).
#DesignerProperty: Key: FloatExample, DisplayName: Float Test, FieldType: Float, DefaultValue: 0, Description: Example of a Float property.
In fact it also suffers from the typical float value storage problem (0.15 ends up as 0.15000000596046448) . I would probably use a string value and cast it to a Double when reading.