For each Column..
There is a EditOptions.DefaultValue.Type drop down
This has to be manually set, but could be automatic when linked to an active dataset when adding columns
Eg if fieldtype is ftdouble then set the type to double and default to 0
otherwise when using the add Icon and the the user does not fill the field in then there is an error
"" is not a valid No.
This goes for other data types as well.
Also, the formatter can be set automatically eg gcfnumber for floats , gcfinteger for integers etc
Also if its a number , then editrules.number could get automatically ticked