Scripting - Why do i get messages like : "can not cast to numeric value" ?

This is because you have a script which accesses a datasourcefield which is DBNull (Nothing) or just the wrong type. If you are pulling the data with GetData("...") then you simply can use Data("...") to resolve this. When working with DataBand (eg. dataBand1("Value")) or Data("...") then the following conversion is done automatically for you:

• Column Type String and Field is DBNull -> Value = ""
• Column Type Numeric and Field is DBNull -> Value = 0
• For Colum Type Date there is no automatic conversion.