On your own risk:

If you want to hack the module, you can change the datatype of the column inputsettings in the table  userdefinedfield from nvarchar(2000) to nvarchar(max). In addition, you need to remove maxLength=2000 in the textbox with id=txtInputSettings in configuration.ascx.  Please check also the SP UserDefinedTable_AddField and UserDefinedTable_UpdateField. If you don't know what I am talking about, don't touch anything. I cannot and will not assist any further in a unsuported modification.

Make a backup in advance! This might be overwritten in a future version, I cannot promise that this gets into the module. Please enter it also as workitem on dnnfnl.codeplex.com!