To set the datatypes on openoffice you could try to do this:
After each column name you could put a "," and then indicates the type. For example, if you want to set the datatype of the column "FIELD1" to character, you would put this on the first field: "FIELD1,C"
Then, if you want to set the size of the column you put other "," and set the number of characters. For example, if the "FIELD1" column will have 7 characters you put "FIELD1,C,7" on the first field.